DL105 Micro PLC. User Manual (2003)

3-10

High-speed Input and Pulse Output Features

Calculating Your

The preset values occupy two data words each. They can range in value from 0000

Preset Values

0000 to 9999 9999, just like the high-speed counter value. All twenty-four values are

absolute values, meaning that each one is an offset from the counter zero value.

The preset values must be individually derived for each application. In the industrial

lathe diagram below, the PLC monitors the position of the lead screw by counting

pulses. At points A, B, and C along the linear travel, the cutter head pushes into the

work material and cuts a groove.

PLC

Industrial Lathe

B C

Counter

Motor

Device

X0, counter clock

Start

The timing diagram below shows the duration of each equal relay contact closure.

Each contact remains on until the next one closes. All go off when the counter resets.

Equal Relays

SP540

SP541

SP542

NOTE: Each successive preset must have a greater value than the previous preset

value. In the industrial lathe example, B>A and C>B.

X Input

The configurable discrete input options for High-Speed Counter Mode are listed in

Configuration

the table below. Input X0 is dedicated for the counter clock input. Inputs X1 and X3

can only be filtered inputs. The section on Mode 60 operation at the end of this

chapter describes programming the filter time constants. Input X2 can be configured

as the counter reset, with or without the interrupt option. The interrupt option allows

the reset input (X2) to cause an interrupt like presets do, but there is no SP relay

contact closure (instead, X2 will be on during the interrupt routine, for 1 scan). Or

finally, X2 may be left simply as a filtered input like X1 and X3.

Input

Configuration

Function

Hex Code

Required

V7634

Counter Clock

0001

V7635

Filtered Input

xx06 (xx = filter time)

V7636

Counter Reset (no interrupt)

0007

Counter Reset (with interrupt)

0107

FIltered Input

xx06 (xx = filter time)

V7637

FIltered Input

xx06 (xx = filter time)

DL105 PLC User Manual, 2nd Edition, Rev. A

3-11

High-Speed Input and Pulse Output Features

Writing Your

You may recall that the counter instruction is a standard instruction in the DL105

Control Program

instruction set. Refer to the figure below. The mnemonic for the counter is UDC

(up-down counter).The DL105 can have up to 64 counters, labeled CT0 through

CT77. The high speed counter in the HSIO circuit is accessed in ladder logic by using

UDC CT76. It uses counter registers CT76 and CT77 exclusively when the HSIO

mode 10 is active (otherwise, CT76 and CT77 are available for standard counter

use). The HSIO counter needs two registers because it is a double-word counter. It

has three inputs as shown. The first input (Enable) allows counting when active. The

middle input (Preload) allows you to change the current count. The bottom signal is

the reset. The preload input must be off while the counter is counting.

Standard Counter Function

HSIO Counter Function

UP Count

UDC CTxx

Enable Input

UDC CT76

DOWN Count

Preload Input

Kxxxxxxxx

Reset Input

D Counts UP and DOWN

D Counts UP only

D Preload counter by write to value

D Can use Preload input to change count

D Reset input is internal only

D Reset may be internal or external

The next figure shows how the HSIO counter will appear in a ladder program. Note

that the Enable Interrupt (ENI) command must execute before the counter value

reaches the first preset value. We do this at powerup by using the first scan relay.

When using the counter but not the presets and interrupt, we can omit the ENI.

DirectSOFT32

SP0

ENI

Required

Enable Input

UDC CT76

Preload Input

Kxxxxxxxx

Reset Input

Preset Range:

1-99999999

When the enable input is energized, the high-speed counter will respond to pulses

on X0 and increment the counter at CT76 - CT77. The reset input contact behaves in

a logical OR fashion with the physical reset input X2 (when selected). So,the high

speed counter can receive a reset form either the contact(s) on the reset rung in the

ladder, OR the external reset X2 if you have configured X2 as an external reset.

Program Example: The following example is the simplest way to use the high-speed counter, which

Counter Without

does not use the presets and special relays in the interrupt routine. The program

Preset

configures the HSIO circuit for Mode 10 operation, so X0 is automatically the counter

clock input. It uses the Compare-double (CMPD) instruction to cause action at

certain count values. Note that this allows you to have more than 24 “presets”.Then it

configures X2 to be the external reset of the counter.

DL105 PLC User Manual, 2nd Edition, Rev. A

3-12

High-speed Input and Pulse Output Features

Program

DirectSOFT32

Example Cont’d

First Scan Only

SP0

Load constant K10 into the accumulator. This

selects Mode 10 as the HSIO mode.

K10

Mode 10

Output the constant K10 to V7633, the

OUT

location of HSIO Mode select register.

V7633

Load the constant required to configure X0 as

the counter clock.

Output the constant K1 to V7634, the location of

OUT

the setup parameter for X0.

V7634

Load the constant required to configure X2 as

Configure

an external reset without interrupt.

Inputs

Output the constant K7 to V7636, the location of

OUT

the setup parameter for X2.

V7636

Load the constant required to configure inputs

as filtered inputs.

K1006

Output the constant K1006 to V7635, the location

OUT

of setup parameter for X1.

V7635

Output the constant K1006 to V7637, the location

OUT

of setup parameter for X3.

V7637

SP1

UDC

CT76

CT76 is the HSIO counter. The first rung’s SP1

always enables the counter. The preload contact in

SP1

the middle is always off. The third rung’s Reset

Kxxxxxxxx

input is always off, because we will use the

external reset.

SP1

Load the current count of the HSIO counter in

LDD

V1076 and V1077 into the accumulator

V1076

Use the Compare-double instruction to compare

CMPD

the double word in the accumulator to the constant

K309482

SP62

OUT

The execution of the above CMPD instruction turns

on special relay contact SP62 if the current count

is greater than the comparison number (K309482).

END

END coil marks the end of the main program.

The compare double instruction above uses the current count of the HSIO counter to

turn on Y0. This technique can make more than 24 comparisons, but it is scan-time

dependent. However, use the 24 built-in presets with the interrupt routine if your

application needs a very fast response time, as shown in the next example.

DL105 PLC User Manual, 2nd Edition, Rev. A

3-13

High-Speed Input and Pulse Output Features

Counter With

The following example shows how to program the HSIO circuit to trigger on three

Presets

preset values. You may recall the industrial lathe example from the beginning of this

chapter. This example program shows how to control the lathe cutter head to make

Program Example

three grooves in the work-piece at precise positions. When the lead screw turns, the

counter device generates pulses which the DL105 can count. The three preset

variables A, B, and C represent the positions (number of pulses) corresponding to

each of the three grooves.

Preset Data

V2320

0000

1500

Industrial Lathe

V2322

0000

3780

V2324

0000

4850

B C

V2326

0000

FFFF

I/O

X4 - Cutter head extended

Counter

Assignments

X5 - Cutter head retracted

Device

Y0 - Lead screw motor

Start

Y1 - Cutter head solenoid

Cutter head

Lead screw

DirectSOFT32

SP0

Enable Interrupts before reaching a preset

ENI

generates an interrupt. Special Relay SP0 is on

during the first CPU scan.

SP0

Load constant K10 into the accumulator. This

selects Mode 10 as the HSIO mode.

K10

Output this address to V7633, the location of

OUT

V7633

HSIO Mode select register.

Load the constant required to configure X0 as

the counter clock.

Output the constant K1 to V7634, the location of

OUT

the setup parameter for X0.

V7634

Load the constant required to configure X2 as

Select Mode 10

an external reset with interrupt.

K107

Output the constant to V7636, the location of the

OUT

setup parameter for X2.

V7636

Load the octal address O2320 into the

LDA

accumulator. This instruction automatically

O2320

converts the address into hex.

OUT

Output this address to V7630, the location of

V7630

the pointer to the Preset Table.

SP0

Load the preset A value into the accumulator.

LDD

K1500

Load Presets

Output the accumulator contents to the memory

OUTD

location for preset 1.

V2320

Load the preset B value into the accumulator.

LDD

K3780

Output the accumulator contents to the memory

OUTD

V2322

location for preset 2.

DL105 PLC User Manual, 2nd Edition, Rev. A

3-14

High-speed Input and Pulse Output Features

Load the preset C value into the accumulator.

LDD

K4850

Output the accumulator contents to the memory

OUTD

location for preset 3.

V2324

Load the constant Kffff into the accumulator. This

LDD

value represents the end of the preset list.

Kffff

Output the accumulator contents to the memory

OUTD

V2326

location for preset 4 (end of preset marker).

SP1

UDC

CT76

CT76 is the HSIO counter. The first rung’s SP1

always enables the counter. The preload contact in

SP1

the middle is off (unused in this example).

Kxxxxxxxx

SP1

The third rung’s Reset input is normally off,

because we will use the external reset. You can

SP0

optionally reset the counter value on each powerup

using the SP0 contact.

RST

Input X4 energizes when the groove has finished

cutting. So, we retract the cutter head.

SET

Turn lead screw on again, after cutter head has

retracted.

END

END coil marks the end of the main program.

The INT label marks the beginning of the interrupt

INT

service routine program.

SP540

Preset 1

Inside the interrupt service routine, we turn OFF the

RST

lead screw motor immediately.

SP541

These special “equal” relays turn on individually as

Preset 2

the corresponding preset is reached. In this

SET

application, each results in the cutting of a groove

SP542

(Y1), so they are logically ORed together.

Preset 3

C10

SET

Input X2 will be energized inside the interrupt

routine if X2 external interrupt was the source.

IRT

Return from the interrupt service routine.

Some applications will require a different type of action at each preset. It is possible

for the interrupt routine to distinguish one preset event from another, by turning on a

unique output for each equal relay contact SPxxx. We can determine the source of

the interrupt by examining the equal relay contacts individually, as well as X2. The X2

contact will be on (inside the interrupt routine only) if the interrupt was caused by the

external reset, X2 input.

DL105 PLC User Manual, 2nd Edition, Rev. A

3-15

High-Speed Input and Pulse Output Features

Counter With

The following example shows how you can preload the current count with another

Preload

value. When the preload command input (X4 in this example) is energized, we

disable the counter from counting with C0. Then we write the value K3000 to the

Program Example

count register (V1076-V1077). By pulsing C1 on, we preload the current count of the

counter with K3000. When the preload command (X4) is turned off, the counter

resumes counting any pulses, but now starting from K3000.

DirectSOFT32

SP0

Load constant K10 into the accumulator. This

selects Mode 10 as the HSIO mode.

K10

Output this address to V7633, the location of

Select Mode 10

OUT

HSIO Mode select register.

V7633

Load the constant required to configure X0 as

the counter clock.

Output the constant K1 to V7634, the location of

OUT

the setup parameter for X0.

V7634

Load the constant required to configure X2 as

an external reset with interrupt.

K107

Output the constant to V7636, the location of the

OUT

setup parameter for X2.

V7636

SET

Set C0 on at powerup to enable counting.

UDC

CT76

CT76 is the HSIO counter. The first rung’s C0

contact enables the counter. The preload contact

in the middle is off until the logic near the end of

K99999999

this program turns it on.

The third rung’s Reset input is normally off,

because we will use the external reset. You can

SP0

optionally reset the counter value on each powerup

using the SP0 contact.

When the preload request is made, the user turns

on X4. First we disable counting by resetting C0,

RST

the counter’s enable input.

Load the BCD value K3000 into the

LDD

accumulator.

K3000

Output the constant to V1076/V1077, the location

OUTD

of the accumulated count for CT76.

V1076

Generate a preload counter input pulse, which

causes the counter to preload from V1076-V1077.

Enable the counter by setting C0, when the

SET

preolad pulse on C1 has occurred (C1 is off).

END

END coil marks the end of the main program.

DL105 PLC User Manual, 2nd Edition, Rev. A

3-16

High-speed Input and Pulse Output Features

Troubleshooting

If you’re having trouble with Mode 10 operation, please study the following

Guide for Mode 10

symptoms and possible causes. The most common problems are listed below.

Symptom: The counter does not count.

Possible causes:

1. Field sensor and wiring - Verify that the encoder, proximity switch,or

counter actually turns on and illuminates the status LED for X0. The

problem could be due to sinking-sourcing wiring problem, etc. Remember

to check the signal ground connection. Also verify that the pulse on-time is

long enough for the PLC to recognize it.

2. Configuration - make sure all of the configuration parameters are correct.

V7633 must be set to 10, and V7634 must be set to 1 to enable the HSIO

counter mode.

3. Stuck in reset - check the input status of the reset input, X2. If X2 is on, the

counter will not count because it is being held in reset.

4. Ladder program - make sure you are using counter CT76 in your

program. The top input is the enable signal for the counter. It must be on

before the counter will count. The middle input is the preload input and must

be off for the counter to count. The bottom input is the counter reset, and

must be off during counting.

Symptom: The counter counts but the presets do not function.

Possible causes:

1. Configuration - Ensure the preset values are correct. The presets are

32-bit BCD values having a range of 0 to 99999999. Make sure you write all

32 bits to the reserved locations by using the LDD and OUTD instructions.

Use only even-numbered addresses, from V2320 to V2376. If using less

than 24 presets, be sure to place “0000FFFF” in the location after the last

preset used.

2. Interrupt routine - Only use Interrupt #0. Make sure the interrupt has been

enabled by executing an ENI instruction prior to needing the interrupt. The

interrupt routine must be placed after the main program, using the INT label

and ending with an interrupt return IRT.

3. Special relays - Check the special relay numbers in your program. Use

SP540 for Preset 1, SP541 for Preset 2, etc. Remember that only one

special equal relay contact is on at a time. When the counter value reaches

the next preset, the SP contact which is on now goes off and the next one

turns on.

Symptom: The counter counts up but will not reset.

Possible causes:

1. Check the LED status indicator for X2 to make sure it is active when you

want a reset. Or, if you are using an internal reset, use the status mode of

DirectSOFT32 to monitor the reset input to the counter.

DL105 PLC User Manual, 2nd Edition, Rev. A

3-17

High-Speed Input and Pulse Output Features

Mode 20: Quadrature Counter

Purpose

The counter in the HSIO circuit can count two quadrature signal pulses instead of a

single pulse train (mode 10 operation). Quadrature signals are commonly generated

from incremental encoders, which may be rotary or linear. The quadrature counter

has a range from 0 to 99999999, and can count at up to a 5 kHz rate, using CT76 and

CT77. Unlike Mode 10 operation, the quadrature counter can count UP or DOWN,

but does not feature automated preset values or “interrupt on external reset”

capability. However, you have the standard ladder instruction preset of CT76.

Functional Block

The diagram below shows HSIO functionality in Mode 20. When the lower byte of

Diagram

HSIO Mode register V7633 contains a BCD “20”, the quadrature counter in the HSIO

circuit is enabled. Input X0 is dedicated to the Phase A quadrature signal, and input

X1 receives Phase B signal. X2 is dedicated to reset the counter to zero value when

energized. X3 can only be a regular filtered input in Mode 20.

DL105

Output Circuit

PLC

Y0, Y1

Y2 - Y7

HSIO

CPU

I/O data

COUNTER

VĆmemory

Mode Select

Phase

V7633

xx20

FILTER

B Reset

X4- X11

Input Circuit

Quadrature

Quadrature encoder signals contain position and direction information, while their

Encoder Signals

frequency represents speed of motion. Phase A and B signals shown below are

phase-shifted 90 degrees, thus the quadrature name. When the rising edge of

Phase A precedes Phase B’s leading edge (indicates clockwise motion by

convention), the HSIO counter counts UP. If Phase B’s rising edge precedes Phase

A’s rising edge (indicates counter-clockwise motion), the counter counts DOWN.

90° phase shift

Leading Edge Signal

Clockwise sequence

Phase A

Phase B

Counterclockwise sequence

Phase A

Phase B

one cycle

Leading Edge Signal

DL105 PLC User Manual, 2nd Edition, Rev. A

3-18

High-speed Input and Pulse Output Features

A general wiring diagram for encoders to the DL105 in HSIO Mode 20 is shown

Wiring Diagram

below. Encoders with sinking outputs (NPN open collector) are probably the best

choice for interfacing. If the encoder sources to the inputs, it must output 12 to 24

VDC. Note that encoders with 5V sourcing outputs will not work with DL105 inputs.

Signal Common

Phase B

DC Supply

Phase A

Encoder Input Wiring

Encoder

Interfacing to

The DL105’s DC inputs are flexible in that they detect current flow in either direction,

Encoder Outputs

so they can be wired to an encoder with either sourcing or sinking outputs. In the

following circuit, an encoder has open-collector NPN transistor outputs. It sinks

current from the PLC input point, which sources current. The power supply can be

the +24VDC auxiliary supply or another supply (+12VDC or +24VDC), as long as the

input specifications are met.

Encoder Output,

(one phase)

Phase A or B Input

Output

Input

(sinking)

(sourcing)

12Ć24 VDC Supply

Ground

Common

In the next circuit, an encoder has open-emitter PNP transistor outputs. It sources

current to the PLC input point, which sinks the current back to ground. Since the

encoder sources current, no additional power supply is required. However, note that

the encoder output must be 12 to 24 volts (5V encoder outputs will not work).

Encoder Output,

(one phase)

Phase A or B Input

+12 to 24VDC

Input

(sinking)

Output (sourcing)

Ground

Common

DL105 PLC User Manual, 2nd Edition, Rev. A

3-19

High-Speed Input and Pulse Output Features

Recall that V7633 is the HSIO Mode Select register. Refer to the diagram below. Use

Setup for Mode 20

BCD 20 in the lower byte to select High-Speed Counter Mode. Use BCD 00 or 20 in

the upper byte as required. Combine the two bytes into a data word “xx20”, for writing

to V7633.

Memory Location V7633

Bits

Miscellaneous Setup (BCD)

HSIO Mode Setup (BCD)

00 = Power Up in Previous Mode

20 = Power Up in Run Mode Always

20 = Quadrature Counter

Choose the most convenient method of programming V7633 from the following:

S Include load and out instructions in your ladder program

S DirectSOFT32’s memory editor

S Use the Handheld Programmer D2-HPP

We recommend using the first method above so that the HSIO setup becomes an

integral part of your application program. An example program later in this section

shows how to to this.

X Input

The configurable discrete input options for High-Speed Counter Mode are listed in

Configuration

the table below. Input X0 is dedicated for Phase A, and input X1 is for Phase B. Input

X2 is the reset input to the quadrature counter, but it does not cause an interrupt.

Input X3 can only be a filtered input. The section on Mode 60 operation at the end of

this chapter describes programming the filter time constants.

Input

Configuration

Function

Hex Code

Required

V7634

Phase A

0012

V7635

Phase B

0000

V7636

Counter Reset (no interrupt)

0007

V7637

Filtered Input

xx06 (xx = filter time)

DL105 PLC User Manual, 2nd Edition, Rev. A

3-20

High-speed Input and Pulse Output Features

Writing Your

You may recall that the Up-Down counter instruction is standard in the DL105

Control Program

instruction set. Refer to the figure below. The mnemonic for the counter is UDC

(up-down counter).The DL105 can have up to 64 counters, labeled CT0 through

CT77. The quadrature counter in the HSIO circuit is accessed in ladder logic by

using UDC CT76. It uses counter registers CT76 and CT77 exclusively when the

HSIO mode 20 is active (otherwise, CT76 and CT77 are available for standard

counter use). The HSIO counter needs two registers because it is a double-word

counter. It also has three inputs as shown, but they are redefined. The first input is

the enable signal, the middle is a preload (write), and the bottom is the reset. The

enable input must be on before the counter will count. The preload input allows you

to write a new value to the current count. The enable input must be off during a

preload.

Standard Counter Function

HSIO Counter Function

UP Count

UDC CTxx

Enable Input

UDC CT76

DOWN Count

Preload Input

Kxxxxxxxx

Reset Input

D Counts UP and DOWN

D Counts UP and DOWN (from X0, X1)

D Preload counter by write to value

D Can use Preload input to change count

D Reset input is internal only

D Reset may be internal or external

The next figure shows the how the HSIO quadrature counter will appear in a ladder

program.

Enable Input

UDC CT76

Preload Input

Kxxxxxxxx

Reset Input

Preset Range:

-8,388,608 to

+8,388,607

When the enable input is energized, the counter will respond to quadrature pulses

on X0 and X1, incrementing or decrementing the counter at CT76 - CT77. The reset

input contact behaves in a logical OR fashion with the physical reset input X2. This

means the quadrature counter can receive a reset from either the contact(s) on the

reset rung in the ladder, OR the external reset X2.

Quadrature

Since presets are not available in quadrature counting, this mode is best suited for

simple counting and measuring. The example program on the following page shows

Counter w/Preload

how to configure the quadrature counter. The program configures the HSIO circuit

Program Example

for Mode 20 operation, so X0 is Phase A and X1 is Phase B clock inputs.

DL105 PLC User Manual, 2nd Edition, Rev. A

3-21

High-Speed Input and Pulse Output Features

Program

DirectSOFT32

Example Cont’d

SP0

Load constant K20 into the accumulator. This selects

Mode 20 as the HSIO mode.

K20

Output this address to V7633, the location of the HSIO

Select Mode 20

OUT

Mode select register.

V7633

Load the constant required to configure X0 as Phase A

input.

K12

Output the constant to V7634, the location of the setup

OUT

V7634

Load the constant required to configure X1 as Phase B

input.

Output the constant to V7635, the location of the setup

OUT

V7635

Load the constant required to configure X2 as an external

reset.

Output the constant to V7636, the location of the setup

OUT

V7636

Load the constant required to configure X3 as a filtered

discrete input with a 10 mS time constant.

K1006

Output the constant to V7637, the location of the setup

OUT

V7637

SET

Set C0 on at powerup to enable counting.

UDC

CT76

CT76 is the HSIO quadrature counter. The first rung’s SP1

always enables the counter. The preload contact in the

middle is controlled by the logic below this counter

Kxxxxxxxx

instruction.

The third rung’s Reset input is normally off,

because we will use the external reset. You can

SP0

optionally reset the counter value on each powerup

using the SP0 contact.

SP1

Load the current value of the counter into the accumulator

LDD

on each scan.

V1076

Compare the value in the accumulator with the constant

Select Mode 20

CMPD

K44292. If they are equal, the SP61 contact will be

K44292

turned on.

SP61

Set Y1 to ON when the counter reaches our

SET

comparison value.

END

END coil marks the end of the main program..

To preload the counter, just add the following example rungs to the program above.

DL105 PLC User Manual, 2nd Edition, Rev. A

3-22

High-speed Input and Pulse Output Features

Counter Preload

When the preload request is made, the user turns

Program Example

RST^{on X4. First we disable counting by resetting C0,}

the counter’s enable input.

Load the BCD value K3000 into the

LDD

Preload counter

accumulator.

K3000

Output the constant to V1076/V1077, the location

OUTD

V1076

of the accumulated pulse count.

PDcauses the counter to preload from V1076-ich

V1077.

Enable the counter by setting C0, when the

SET

preolad pulse on C1 has occurred (C1 is off).

Troubleshooting

If you’re having trouble with Mode 20 operation, please study the following

Guide for Mode 20

symptoms and possible causes. The most common problems are listed below.

Symptom: The counter does not count.

Possible causes:

1. Field sensor and wiring - Verify that the encoder or other field device

inputs actually turn on and illuminates the status LEDs for X0 and X1. A

standard incremental encoder will visibly, alternately turn on the LEDs for

X0 and X1 when rotating slowly (1 RPM). Or, the problem could be due to a

sinking-sourcing wiring problem, etc. Remember to check the signal

ground connection. Also verify that the pulse on-time, duty cycle, voltage

level, and frequency are within the input specifications.

2. Configuration - make sure all of the configuration parameters are correct.

V7633 must be set to 20, and V7634 must be set to “0012” to enable the

Phase A input, and V7635 must be set to “0000” to enable the Phase B

input.

3. Stuck in reset - check the input status of the reset input, X2. If X2 is on, the

counter will not count because it is being held in reset.

4. Ladder program - make sure you are using counter CT76 in your

program. The top input is the enable signal for the counter. It must be on

before the counter will count. The middle input is the preload input and must

be off for the counter to count. The bottom input is the counter reset, and

must be off during counting.

Symptom: The counter counts in the wrong direction (up instead of down, and visa-versa).

Possible causes:

1. Channel A and B assignment - It’s possible that Channel A and B

assignments of the encoder wires is backwards from the desired

rotation/counting orientation. Just swap the X0 and X1 inputs, and the

counting direction will be reversed.

Symptom: The counter counts up and down but will not reset.

Possible causes:

1. Check the LED status indicator for X2 to make sure it is active when you

want a reset. Also verify the configuration register V7636 for X2 is set to 7.

Or, if you are using an internal reset, use the status mode of DirectSOFT32

to monitor the reset input to the counter.

DL105 PLC User Manual, 2nd Edition, Rev. A

3-23

High-Speed Input and Pulse Output Features

Mode 30: Pulse Output

Purpose

The HSIO circuit in Mode 30 generates

Trapezoidal Profile

output pulse trains suitable for open-loop

Velocity

control of a single-axis motion positioning

system. It generates pulse

(stepper

increment) and direction signals which

Accel

Decel

you can connect to motor drive systems

and perform various types of motion

control. Using Mode 30 Pulse Output, you

Time

can select from three profile types:

S Trapezoidal - Accel Slope to Target Velocity to Decel Slope

S Registration - Velocity to Position Control on Interrupt (also used for

home search moves)

S Velocity Control - Speed and Direction only

The HSIO circuit becomes a high-speed pulse generator (up to 7 kHz) in Mode 30.

By programming acceleration and deceleration values, position and velocity target

values, the HSIO function automatically calculates the entire motion profile. The

figure below shows the DL105 generating pulse and direction signals to the drive

amplifier of a stepper positioning system. The pulses accomplish the profile

independently and without interruption to ladder program execution in the CPU.

Pulse

Stepper

Motor

Direction

DL105 Micro PLC

Drive

Amplifier

In the figure above, the DL105 generates

CCW Pulse

pulse and direction signals. Each pulse

represents the smallest increment of

motion to the positioning system (such as

CW Pulse

one step or micro-step to a stepper

system). Alternatively, the HSIO Pulse

Output Mode may be configured to deliver

counter clock-wise (CCW) and clock-wise

Drive

(CW) pulse signals as shown to the right.

Amplifier

NOTE: The pulse output is designed for open loop stepper motor systems. This, plus

its minimum velocity of 40 pps make it unsuitable for servo motor control.

DL105 PLC User Manual, 2nd Edition, Rev. A

3-24

High-speed Input and Pulse Output Features

Functional Block The diagram below shows HSIO functionality in Mode 30. When the lower byte of

Diagram

HSIO Mode register V7633 contains a BCD “30”, the pulse output capability in the

HSIO circuit is enabled. The pulse outputs use Y0 and Y1 terminals on the output

connector. Remember that the outputs can only be DC type to operate.

DL105

Output Circuit

PLC

(Pulse / CW)

(Direction / CCW)

Y2 - Y7

HSIO

X0 Profile Complete

CPU

PULSE GEN.

Y0 Start Profile

Y1 Preload Position Value

X1, X3 Filtered Inputs

Interrupt

FILTER

VĆmemory

Mode Select

V7633

xx30

not used

X1, X3

X4- X11

Input Circuit

IMPORTANT NOTE: In Pulse Output Mode, X0, Y0, and Y1 references are

redefined or are used differently in two ways. Physical references refer to terminal

screws, while logical references refer to I/O references in the ladder program.

Please read the items below to understand this very crucial point.

Notice the I/O point assignment and usage in the above diagram:

S Physical input X0 is not used, so the terminal screw will not be wired.

However, the HSIO function uses logical reference X0 for “Profile

Complete” contact, which is available for ladder program use.

S X1 and X3 can only be filtered inputs in Pulse Output Mode, and they

are available as input contacts to the ladder program.

S X2 behaves as an external interrupt to the pulse generator for

registration profiles. In other profile modes, it can be used as a filtered

input just like X1 and X3 (registration mode configuration shown above).

S References “Y0” and “Y1” are used in two different ways. At the output

connector, Y0 and Y1 terminals deliver the pulses to the motion system.

The ladder program uses logical references Y0 and Y1 to initiate “Start

Profile” and “Load Position Value” HSIO functions in Mode 30.

Hopefully, the above discussion will explain why some I/O reference names have

dual meanings in Pulse Output Mode. Please read the remainder of this section

with care, to avoid confusion about which actual I/O function is being discussed.

DL105 PLC User Manual, 2nd Edition, Rev. A

3-25

High-Speed Input and Pulse Output Features

Wiring Diagram

The generalized wiring diagram below shows pulse outputs Y0 and Y1 connected to

the drive amplifier inputs of a motion control system.

Pulse Output Wiring

Power Input

Amplifier

Motor

Pulse

Signal Common

Direction

Interfacing to

The pulse signals from Y0 and Y1 outputs will typically go to drive input circuits as

Drive Inputs

shown above. Remember that the DL105’s DC outputs are sinking-only. It will be

helpful to locate equivalent circuit schematics of the drive amplifier. The following

diagram shows how to interface to a sourcing drive input circuit.

Y0, Y1 Pulse Output

Drive Input

Power

+DC pwr

Output

Input

(sinking)

(sourcing)

Common

Ground

The following circuit shows how to interface to a sinking drive input using a pullup

resistor. Please refer to Chapter 2 to learn how to calculate and install Rpullup.

Y0, Y1 Pulse Output

Power

+DC pwr

Drive Input

pullup

(sourcing)

(sinking)

Output

Input

R input

(sinking)

Supply

Common

Ground

DL105 PLC User Manual, 2nd Edition, Rev. A

3-26

High-speed Input and Pulse Output Features

Motion Profile

The motion control profiles generated in Pulse Output Mode have the following

Specifications

specifications:

Parameter

Specification

Profiles

Trapezoidal - Accel Slope / Target Velocity / Decel Slope

Registration - Velocity to Position Control on Interrupt

Velocity Control - Speed and Direction only

Position Range

-88388608 to 88388607

Positioning

Absolute / relative command

Velocity Range

40 Hz to 7 kHz

V-memory registers

V2320 to V2325 (Profile Parameter Table)

Current Position

CT76 and CT77 (V1076 and V1077)

Physical I/O

The configurable discrete I/O options for Pulse Output Mode are listed in the table

Configuration

below. Physical input X0 is not available, because the CPU uses logical X0 contact to

sense “profile complete”. Therefore, V7634 is put to another use: selecting

pulse/direction or CCW/CW modes for the pulse outputs. Inputs X1 and X3 can only

be filtered inputs. Input X2 is dedicated as the external interrupt for use in registration

mode.

Physical

Configuration

Function

Hex Code

Input

Required

–

V7634

Y0 = Pulse

0103

Y1 = Direction

Y0 = CW Pulse

0003

Y1 = CCW Pulse

V7635

Filtered Input

xx06 (xx = filter time)

V7636

External Interrupt

1006

V7637

Filtered Input

xx06 (xx = filter time)

Logical I/O

The following logical I/O references define functions that allow the HSIO

Functions

communicate with the ladder program.

Logical

Function

I/O

Profile Complete - the HSIO turns on X0 to the CPU when the

profile completes. Goes back off when Start Profile (Y0) turns on.

Start Profile - the ladder program turns on Y0 to start motion. If

turned off before the move completes, motion stops. Turning it on

again will start another profile, unless the current position equals

the target position.

Preload Position Value - if motion is stopped and Start Profile is off,

you can load a new value in CT76/CT77, and turn on Y1. At that

transition, the value in CT76/CT77 becomes the current position.

DL105 PLC User Manual, 2nd Edition, Rev. A

3-27

High-Speed Input and Pulse Output Features

Setup for Mode 30

Recall that V7633 is the HSIO Mode Select register. Refer to the diagram below. Use

BCD 30 in the lower byte to select Pulse Output Mode. Use BCD 00 or 20 in the upper

byte as required. Combine the two bytes into a data word “xx30”, for writing to

V7633.

Memory Location V7633

Bits

Miscellaneous Setup (BCD)

HSIO Mode Setup (BCD)

00 = Power Up in Previous Mode

20 = Power Up in Run Mode Always

30 = Pulse Output

Choose the most convenient method of programming V7633 from the following:

S Include load and out instructions in your ladder program

S DirectSOFT32’s memory editor

S Use the Handheld Programmer D2-HPP

We recommend using the first method above so that the HSIO setup becomes an

integral part of your application program. An example program later in this section

shows how to to this.

Profile / Velocity

The first location in the Profile Parameter Table stores two key pieces of information.

Select Register

The upper four bits (12-15) select the type of profile required. The lower 12 bits

(0-11) select the Target Velocity.

Memory Location V2320 (default)

Bits

Profile Select (BCD)

Target Velocity Value

0 = Trapezoidal Profile, Absolute Position

Range = 4 to 700, representing

8 = Trapezoidal Profile, Relative Position

40 Hz to 7 kHz pulse rate

9 = Registration Profile, Relative Position

2 = Velocity Profile

The ladder program must program this location before initiating any of the three

profiles. The LD and OUT instruction will write all 16 bits, so be sure to fully specify

the full four-digit BCD value for the Position / Velocity Select Register each time.

The absolute and relative selection determines how the HSIO circuit will interpret

your specified target position. Absolute position targets are referenced to zero.

Relative position targets are referenced to the current position (previous target

position). You may choose whichever reference method that is most convenient for

your application.

DL105 PLC User Manual, 2nd Edition, Rev. A

3-28

High-speed Input and Pulse Output Features

Profile

V7630 is a pointer location which points to

Profile Table Pointer

Parameter Table

the beginning of the Profile Parameter

V7630

2320

Table. The default starting location for the

profile parameter table is V2320.

Profile Parameter Table

However, you may change this by

V2320

xxxx

programming a different value in V7630.

V2321

xxxx

Remember to use the LDA (load address)

V2323

xxxx

instruction, converting octal into hex.

V2324

xxxx

The HSIO uses the next V-memory

V2325

xxxx

parameter table to indicate profile errors.

Pulse Output Error Code

See the error table at the end of this

section for error code definitions.

V2326

00xx

Trapezoidal Profile

V-Memory

Function

Range

Units

V2320, bits 12-15

Trapezoidal Profile

0=absolute,

8=relative

V2320, bits 0-11

Target Velocity Value

4 to 700

x 10 pps

V2321/ 2322

Target Position Value

-88388608 to

Pulses

88388607

V2323

Starting Velocity

4 to 100

x 10 pps

V2324

Acceleration Time

1 to 100

x 100 mS

V2325

Deceleration Time

1 to 100

x 100 mS

V2326

Error Code

(see end of section)

Registration Profile

V-Memory

Function

Range

Units

V2320, bits 12-15

Registration Profile

9=relative

V2320, bits 0-11

Target Velocity Value

4 to 700

x 10 pps

V2321/ 2322

Target Position Value

-88388608 to

Pulses

88388607

V2323

Starting Velocity

4 to 100

x 10 pps

V2324

Acceleration Time

1 to 100

x 100 mS

V2325

Deceleration Time

1 to 100

x 100 mS

V2326

Error Code

(see end of section)

Velocity Profile

V-Memory

Function

Range

Units

V2320

Velocity Profile

2000 only

V2321/ 2322

Direction Select

80000000=CCW,

Pulses

0=CW

V2323

Velocity

4 to 700

x 10 pps

V2326

Error Code

(see end of section)

DL105 PLC User Manual, 2nd Edition, Rev. A

3-29

High-Speed Input and Pulse Output Features

Choosing the

Pulse Output Mode generates three types of motion profiles. Most applications use

Profile Type

one type for most moves. However, each move can be different if required.

S Trapezoidal - Accel Slope to Target Velocity to Decel Slope

S Registration - Velocity to Position Control on Interrupt

S Velocity Control - Speed and Direction only

Trapezoidal

The trapezoidal profile is the most

Trapezoidal Profile

Profile Defined

common positioning profile. It moves the

Velocity

load to a pre-defined target position by

Fixed Velocity

creating a move profile. The acceleration

slope is applied at the starting position.

Accel

Decel

The deceleration slope is applied

backwards from the target position. The

remainder of the move in the middle is

Time

spent traveling at a defined velocity.

Start position Target position

Trapezoidal profiles are best for simple point-to-point moves, when the distance

between the starting and ending positions of the move is known in advance.

Registration and

Registration profiles solve a class of

Home Search

motion control problems. In some

Profiles Defined

applications, product material in work

moves past a work tool such as a drill

Scrap

Finished part area

station. Shown to the right, registration

Area

marks on the scrap area of the work-piece

allow a machine tool to register its position

relative to the rectangle, to drill properly.

Home search moves allow open-loop

direction of motion

motion systems to re-calibrate (preload)

Registration marks

the current position value at powerup.

Registration profiles are a combination of

Registration Profile

velocity and position control modes. The

Velocity

Position

move begins by accelerating to a

Control

Velocity

programmed velocity. The velocity is

sustained and the move is of indefinite

duration. When an external interrupt

signal occurs

(due to registration

Accel

Decel

sensing), the profile switches from velocity

to position control. The move ends by

continuing motion a pre-defined distance

past the interrupt point (such as a drill hole

Target position

location). The deceleration ramp is

Interrupt

applied in advance of the target position.

Velocity Profile

The velocity profile controls only the

Velocity Profile

Velocity

Defined

direction and speed of motion. There is no

target position specified, so the move can

be of indefinite length. Only the first

velocity value needs to be defined. The

remaining velocity values can be created

while motion in in progress. Arrows in the

profile shown indicate velocity changes.

Time

DL105 PLC User Manual, 2nd Edition, Rev. A

3-30

High-speed Input and Pulse Output Features

Trapezoidal Profile Operation

The trapezoidal profile is best suited for simple point-to-point moves, when the target

Trapezoidal Profile

position is known in advance. Starting velocities must be within the rage of 40 pps to

Applications

1 kpps. The remainder of the profile parameters are in the profile parameter table.

Trapezoidal Profile

Velocity

Target Velocity

Accel

Decel

Starting

Velocity

Time

Start position

Target position

Start

Profile

Complete

The time line of signal traces below the profile indicates the order of events.

The HSIO uses logical output Y0 as the Start input to the HSIO, which starts the

profile. Immediately the HSIO turns off the Profile Complete signal (logical X0), so

the ladder program can monitor the progress of the move. Typically a ladder

program will monitor this bit so it knows when to initiate the next profile move.

If you are familiar with motion control, you’ll notice that we do not have to specify the

direction of the move. The HSIO function examines the target position relative to the

current position, and automatically outputs the correct direction information to the

motor drive.

Notice that the motion accelerates immediately to the starting velocity. This segment

is useful in stepper systems so we can jump past low speed areas when low-torque

problems or a resonant point in the motor might cause a stall. (When a stepper motor

stalls, we have lost the position of the load in open-loop positioning systems).

However, is is preferable not to make the starting velocity too large, because the

stepper motor will also “slip” some pulses due to the inertia of the system.

When you need to change the current position value, use logical Y1 output coil to

load a new value into the HSIO counter. If the ladder program loads a new value in

CT76/CT77 (V1076/V1077), then energizing Y1 will copy that value into the HSIO

circuit counter. This must occur before the profile begins, because the HSIO ignores

Y1 during motion.

DL105 PLC User Manual, 2nd Edition, Rev. A

3-31

High-Speed Input and Pulse Output Features

Trapezoidal Profile

The trapezoidal profile we want to perform is drawn and labeled in the following

Program Example

figure. It consists of a non-zero starting velocity, and moderate target velocity.

Trapezoidal Profile

Velocity

Target Velocity = 1 kHz

Accel = 2 sec

Decel = 4 sec

Starting

Velocity = 40

Time

Start position

Target position = 5000

The following program will realize the profile drawn above, when executed. The

beginning of the program contains all the necessary setup parameters for Pulse

Output Mode 30. We only have to do this once in the program, so we use first-scan

contact SP0 to trigger the setup.

DirectSOFT32

SP0

Load constant K30 into the accumulator. This selects

Mode 30 as the HSIO mode.

K30

Mode 30

Output the constant to V7633, the location of the HSIO

OUT

Mode select register.

V7633

Load the octal address of the beginning of the Profile

Locate Parameter

LDA

Parameter Table. The LDA instruction converts this to a

O2320

Table (optional)

hex number in the accumulator.

Output this address to V7630, the location of the pointer

OUT

to the Profile Parameter Table.

V7630

Load the constant K103 which is required to select

Select Pulse /

pulse and direction for physical Y0 and Y1 functions,

K103

respectively (use K3 if your application needs CCW

Direction

and CW).

OUT

Output this constant to V7634, configuring the pulse

V7634

output type.

Filtered Inputs

Load the constant K1006 which is required to select

filtered inputs with a 10 mS filter time constant.

K1006

OUT

Output this constant to V7635, configuring X1.

V7635

OUT

Output this constant to V7636, configuring X2.

V7636

OUT

Output this constant to V7637, configuring X3.

V7637

DL105 PLC User Manual, 2nd Edition, Rev. A

3-32

High-speed Input and Pulse Output Features

Program

Example Cont’d

SP0

Load the constant K100 which is required to select

Trapzoidal Profile, absolute positioning, and a target

K100

velocity of 1 kHz.

Profile / Target

Output this constant to V2320, the location of the Profile

OUT

Select / Starting Velocity setup register.

Velocity

V2320

Load the constant K5000 which selects a target

Target Position

LDD

position of 5000 pulses. Don’t forget to use double

K5000

word size (8-digit BCD position value).

Output this constant to V2321 and V2322, the location of

OUTD

the Target Position double-word register.

V2321

Load the constant K4 which is required to select a

Starting Velocity

starting velocity of 40 Hz (4 x 10 pps).

Output this constant to V2323, the location of the starting

OUT

velocity parameter register.

V2323

Load the constant K20 which is required to select an

Acceleration

acceleration time of 2 seconds (20 x 100 mS).

K20

Output this constant to V2324, the location of the

OUT

acceleration parameter register.

V2324

Load the constant K40 which is required to select a

Deceleration

deceleration time of 4 seconds (40 x 100 mS).

K40

Output this constant to V2325, the location of the

OUT

deceleration parameter register.

V2325

Start Profile

We use a spare filtered input to allow the operator

OUT

to start the profile. When the operator turns X3 ON,

then OFF, logical output Y0 starts the profile.

Profile Complete

X0 is the logical output of the HSIO to indicate the

OUT

move is complete. We use Y2 to energize an

annunciator that the profile has finished.

Preload

At any time you can write (preload) a new position into the current position value.

Position Value

This often done after a home search (see the registration example programs).

SP0

Load the constant K1000 as the new current position

LDD

value.

K1000

Profile / Target

Output this constant to V1076/V1077 (CTA76/CTA77). the

OUTD

location of the current position value.

Velocity

V1076

PD Turn on Y1 for 1 scan. The off-to-on transition

causes the HSIO to preload the current position

with the value in

DL105 PLC User Manual, 2nd Edition, Rev. A

3-33

High-Speed Input and Pulse Output Features

Registration Profile Operation

Registration

1. In a typical application shown to the

Applications

right, product material in work moves past

a work tool such as a drill. Registration

Scrap

marks on the scrap area of the work-piece

Finished part area

Area

allow a machine tool to register its position

relative to the rectangle, to drill properly.

2. In other examples of registration, the

work piece is stationary and the tool

direction of motion

moves. A drill bit may approach the

Registration marks

surface of a part in work, preparing to drill

a hole of precise depth. However, the drill

bit length gradually decreases due to tool

wear. A method to overcome this is to

detect the moment of contact with the part

surface on each drill, moving the bit into

the part a constant distance after contact.

Detect contact

3. The home search move allows a motion system to calibrate its position on

startup. In this case, the positioning system makes an indefinite move and waits for

the load to pass by a home limit switch. This creates an interrupt at the moment when

the load is in a known position. We then stop motion and preload the position value

with a number which equates to the physical “home position”.

The registration profile begins with only velocity control. When an interrupt pulse

occurs on physical input X2, the starting position is declared to be the present count

(current load position). The velocity control switches to position control, moving the

load to the target position. Note that the minimum starting velocity is 40 pps. This

instantaneous velocity accommodates stepper motors that can stall at low speeds.

Registration Profile

Velocity

Target Velocity

Accel

Decel

Starting

Velocity

Start

Target

Time

position

Start

External Interrupt X2

Profile Complete X0

The time line of signal traces below the profile indicates the order of events. The

CPU uses logical output Y0 to start the profile. Immediately the HSIO turns off the

Profile Complete signal (logical X0), so the ladder program can monitor the move’s

completion by sensing the signal’s on state.

DL105 PLC User Manual, 2nd Edition, Rev. A

3-34

High-speed Input and Pulse Output Features

Registration Profile

The registration profile we want to perform is drawn and labeled in the following

Program Example

figure. It consists of a non-zero starting velocity, and moderate target velocity.

Registration Profile

Velocity

Target Velocity = 1 kHz

Accel = 2 sec

Decel = 4 sec

Starting

Velocity = 40

Time

Start position

Target position = 5000

The following program will realize the profile drawn above, when executed. The first

program rung contains all the necessary setup parameters. We only have to do this

once in the program, so we use first-scan contact SP0 to trigger the setup.

DirectSOFT32

SP0

Load constant K30 into the accumulator. This selects

Mode 30 as the HSIO mode.

K30

Mode 30

Output this constant to V7633, the location of the HSIO

OUT

Mode select register.

V7633

Load the octal address of the beginning of the Profile

Locate Parameter

LDA

Parameter Table. The LDA instruction converts this to a

Table (optional)

O2320

hex number in the accumulator.

Output this address to V7630, the location of the pointer

OUT

to the Profile Parameter Table.

V7630

Load the constant K103 which is required to select

Select Pulse /

pulse and direction for physical Y0 and Y1 functions,

K103

Direction

respectively (your application may use CCW and CW).

Output this constant to V7634, configuring the pulse

OUT

output type.

V7634

Load the constant K2006 which is required to select

Filtered Inputs

filtered inputs with a 20 mS filter time constant.

K2006

Output this constant to V7635, configuring X1.

OUT

V7635

Output this constant to V7637, configuring X3.

OUT

V7637

Load the constant K1006 which is required to select the

external interrupt.

K1006

Output this constant to V7636, configuring X2, the

OUT

registration interrupt input.

V7636

DL105 PLC User Manual, 2nd Edition, Rev. A

3-35

High-Speed Input and Pulse Output Features

Program

Example Cont’d

SP0

Load the constant K9100 which is required to select

Registration Profile, relative positioning, and a target

K9100

velocity of 1 kHz (9xxx times 10 pps).

Profile / Target

Output this constant to V2320, the location of the Profile

OUT

Select / Starting Velocity setup register.

Velocity

V2320

Load the constant K5000 which selects a target

Target Position

LDD

position of 5000 pulses. Don’t forget to use double

K5000

word size (8-digit BCD position value).

Output this constant to V2321 and V2322, the location of

OUTD

the Target Position double-word register.

V2321

Load the constant K4 which is required to select a

Starting Velocity

starting velocity of 40 Hz (4 x 10 pps).

Output this constant to V2323, the location of the starting

OUT

velocity parameter register.

V2323

Load the constant K20 which is required to select an

Acceleration

acceleration time of 2 seconds (20 x 100 mS).

K20

Output this constant to V2324, the location of the

OUT

acceleration parameter register.

V2324

Load the constant K40 which is required to select a

Deceleration

deceleration time of 4 seconds (40 x 100 mS).

K40

Output this constant to V2325, the location of the

OUT

deceleration parameter register.

V2325

Start Profile

SET

We use a spare filtered input to allow the operator

to start the profile. X3 is a momentary Start switch.

When the operator turns X3 ON, logical output Y0

Profile Complete

starts the profile.

OUT

X0 is the logical output of the HSIO to indicate the

move is complete. We use Y2 to energize an

annunciator that the profile has finished. This won’t

occur until after the interrupt from X2 has occurred

and the profile is complete.

RST

The profile will begin when the start input (X3) is given. Then the motion begins an

indefinite move, which lasts until an external interrupt on X2 occurs. Then the motion

continues on for 5000 more pulses before stopping.

DL105 PLC User Manual, 2nd Edition, Rev. A

3-36

High-speed Input and Pulse Output Features

One of the more challenging aspects of motion control is the establishment of actual

Home Search

position at powerup. This is especially true for open-loop systems which do not have

Program Example

a position feedback device. However, a simple limit switch located at an exact

location on the positioning mechanism can provide “position feedback” at one point.

For most stepper control systems, this method is a good and economical solution.

Load

Positioning System

Motor

Limit Switches

CCW limit (X1)

Home limit (X2)

CW limit (X3)

Motion

Numbering System

-3000

-2000

-1000

1000

2000

3000

In the drawing above, the load moves left or right depending on the CCW/CW

direction of motor rotation. The PLC ladder program senses the CCW and CW limit

switches to stop the motor, before the load moves out-of-bounds and damages the

machine. The home limit switch is used at powerup to establish the actual position.

The numbering system is arbitrary, depending on a machine’s engineering units.

At powerup, we do not know whether the load is located to the left or to the right of the

home limit switch. Therefore, we will initiate a home search profile, using the

registration mode. The home limit switch is wired to X2, causing the interrupt. We

choose an arbitrary initial search direction, moving in the CW (left-to-right) direction.

S If the home limit switch closes first, then we stop and initialize the

position (this value is typically “0”, but it may be different if preferred).

S However, if the CW limit switch closes first, we must reverse the motor

and move until the home limit switch closes, stopping just past it.

In the latter case, we repeat the first move, because we always need to make the

final approach to the home limit switch from the same direction, so that the final

physical position is the same in either case!

DirectSOFT32

SP0

Selects Mode 30 as

the HSIO mode.

K30

Filtered Inputs

The constant K2006

Mode 30

OUT

selects a 20 mS filter

K2006

V7633

time constant.

Output this constant to

Locate

Configure the address

OUT

LDA

V7635, configuring X1.

Parameter

O2320

of the parameter table.

V7635

Table (optional)

Output this constant to

OUT

V7637, configuring X3.

V7630

V7637

The constant K1006

Select Pulse /

Configure the Y0 and Y1

selects a 10 mS filter

pulse outputs for pulse

Direction

K1006

K103

time constant.

and direction, respectively.

Output this constant to

OUT

V7636, configuring X2, the

V7636

V7634

registration interrupt input.

DL105 PLC User Manual, 2nd Edition, Rev. A

3-37

High-Speed Input and Pulse Output Features

Profile / Target Velocity

SP0

Add a timer to

Select Registration Profile,

TMR

create a slight

relative positioning, and a

K9100

delay before

target velocity of 1000 pps

reversing motor.

(9xxx times 10 pps).

OUT

V2320

SET

CCW delay done.

Starting Velocity

The constant K4 selects a

starting velocity of 40 Hz

(4 x 10 pps).

SET Start profile again.

CCW past home

OUT

V2323

SET

CCW past home

The constant K20 selects

Acceleration

an acceleration time of 2

Load a small

K20

LDD

seconds (20 x 100 mS).

positive position

K50

count (go CW).

OUT

V2324

OUTD

V2321

Deceleration

We’ll choose the same for

OUT

the deceleration value.

Home Limit found, CW search direction

V2325

X10

C10

Start the home search

RST

Turn off Start Profile.

SET

when X10 turns on.

Search in CW direction

SET^{Go CW back to}

home.

C10

The constant K50 selects

LDD

TMR

Add a timer to

a target position of 50

create a slight

K50

pulses (CW direction).

delay before

reversing motor.

Target Position

OUTD

V2321

Turn on Start Profile,

SET CW delay done.

searching for either the

home limit or the CW limit

SET

(depends on our starting

position).

SET Start profile again.

Set C0 to indicate the CW

SET

Home Limit found, CW search direction

home search has begun.

CW Limit found

C1 C3

RST Turn off Start Profile.

RST

Turn off Start Profile.

Load the constant

LDD

The constant -K200

K0 for our initialized

LDD

selects a target

position.

K80000200

position of -200

pulses, which is in

OUTD

Output this constant

the CCW direction.

V1076

to C1076/V1077.

OUTD

V2321

The CW limit has

SET

been reached.

The home search profile will execute specific parts of the program, based on the

order of detection of the limit switches. Ladder logic sets C0 to initiate a home search

in the CW direction. If the CW limit is encountered, the program searches for home in

the CCW direction, passes it slightly, and does the final CW search for home. After

reaching home, the last ladder rung preloads the current position to “0”.

DL105 PLC User Manual, 2nd Edition, Rev. A

3-38

High-speed Input and Pulse Output Features

Velocity Profile Operation

Velocity Profile

The velocity profile is best suited for applications which involve motion but do not

Applications

require moves to specific points. Conveyor speed control is a typical example.

Velocity Profile

Velocity

Time

Start

Profile

Complete X0

The time line of signal traces below the profile indicates the order of events.

Assuming the velocity is set greater than zero, motion begins when the Start input

(Y0) energizes. Since there is no end position target, the profile is considered in

progress as long as the Start input remains active. The profile complete logical input

to ladder logic (X0) correlates directly to the Start input status when velocity profiles

are in use.

While the Start input is active, the ladder program can command a velocity change

by writing a new value to the velocity register (V2323 by default). The full speed

range of 40 Hz to 7 kHz is available. Notice from the drawing that there are no

acceleration or deceleration ramps between velocity updates. This is how velocity

profiling works with the HSIO. However, the ladder program can command more

gradual velocity changes by incrementing or decrementing the velocity value more

slowly. A counter or timer can be useful in creating your own

acceleration/deceleration ramps. Unless the load must do a very complex move, it is

easier to let the HSIO function generate the accel/decel ramps by selecting the

trapezoidal or registration profiles instead.

Unlike the trapezoidal and registration profiles, you must specify the desired

direction of travel with velocity profiles. Load the direction select register

(V2321/V2322 by default) with 8000 0000 hex for CCW direction, or 0 for CW

direction.

DL105 PLC User Manual, 2nd Edition, Rev. A

3-39

High-Speed Input and Pulse Output Features

The velocity profile we want to perform is drawn and labeled in the following figure.

Velocity Profile

Each velocity segment is of indefinite length. The velocity only changes when ladder

Program Example

logic (or other device writing to V-memory) updates the velocity parameter.

Velocity Profile

Velocity

Time

The following program uses dedicated discrete inputs to load in new velocity values.

This is a fun program to try, because you can create an infinite variety of profiles with

just two or three input switches. The intent is to turn on only one of X1, X2, or X3 at a

time. The beginning of the program contains all the necessary setup parameters for

Pulse Output Mode 30. We only have to do this once in the program, so we use

first-scan contact SP0 to trigger the setup.

DirectSOFT32

SP0

Load constant K30 into the accumulator. This selects

Mode 30 as the HSIO mode.

K30

Mode 30

Output this constant to V7633, the location of the HSIO

OUT

Mode select register.

V7633

Load the octal address of the beginning of the Profile

Locate Parameter

LDA

Parameter Table. The LDA instruction converts this to

O2320

Table (optional)

hex number in the accumulator.

Output this address to V7630, the location of the pointer

OUT

to the Profile Parameter Table.

V7630

Load the constant K103 which is required to select

Select Pulse /

pulse and direction for physical Y0 and Y1 functions,

K103

Direction

respectively (your application may use CCW and CW).

Output this constant to V7634, configuring the pulse

OUT

output type.

V7634

Load the constant K1006 which is required to select

Filtered Inputs

filtered inputs with a 10 mS filter time constant.

K1006

Output this constant to V7635, configuring X1.

OUT

V7635

Output this constant to V7636, configuring X2.

OUT

V7636

Output this constant to V7637, configuring X3.

OUT

V7637

DL105 PLC User Manual, 2nd Edition, Rev. A

3-40

High-speed Input and Pulse Output Features

Program

Example Cont’d

SP0

Load the constant K2000 which is required to select

Velocity Profile. This data word contains no velocity

K2000

information in the case of velocity mode.

Profile / Target

Output this constant to V2320, the location of the Profile

OUT

Select setup register.

Velocity

V2320

Load the constant K80000000 which selects CCW

Select Direction

LDD

direction for Velocity Profiles. Don’t forget to use double

K80000000

word size (8-digit BCD position value).

Output this constant to V2321 and V2322, the location of

OUTD

the Target Position double-word register.

V2321

Load the constant K10 which is required to select an

Set Velocity

initial velocity of 100 pps (uses x10 multiplier).

K10

Output this constant to V2323, the location of the velocity

OUT

parameter register. After the program is running, we can

V2323

write here again, using discrete input switches.

Start Profile

OUT

We use a spare filtered input to allow the operator

to start the profile. When the operator turns X1 ON

and leaves it on, logical output Y0 starts the profile.

Go Slow

Load the constant K50 which is required to select a

velocity of 500 pps when the operator closes X2.

K50

Output this constant to V2323, the location of the velocity

OUT

parameter register. The speed will change immediately.

V2323

Go Moderately

Load the constant K200 which is required to select a

velocity of 2000 pps when the operator closes X3.

K200

Output this constant to V2323, the location of the velocity

OUT

parameter register. The speed will change immediately.

V2323

Go Fast

Load the constant K600 which is required to select a

velocity of 6000 pps when the operator closes X4.

K600

Output this constant to V2323, the location of the velocity

OUT

V2323

parameter register. The speed will change immediately.

DL105 PLC User Manual, 2nd Edition, Rev. A

3-41

High-Speed Input and Pulse Output Features

Pulse Output Error

The Profile Parameter Table starting at V2320 (default location) defines the profile.

Codes

Certain numbers will result in a error when the HSIO attempts to use the parameters

to execute a move profile. When an error occurs, the HSIO writes an error code in

V2326.

Error Code

Error Description

0000

No error

0010

Requested profile type code is invalid (must use 0, 1, 2, 8, or 9)

0020

Target Velocity is not in BCD

0021

Target Velocity is specified to be less than 40 pps

0022

Target Velocity is specified to be greater than 7,000 pps

0030

Target Position value is not in BCD

0040

Starting Velocity is not in BCD

0041

Starting Velocity is specified to be less than 40 pps

0042

Starting Velocity is specified to be greater than 1,000 pps

0050

Acceleration Time is not in BCD

0051

Acceleration Time is zero

0052

Acceleration Time is greater than 10 seconds

0010

Deceleration Time is not in BCD

0010

Deceleration Time is zero

0010

Deceleration Time is greater than 10 seconds

Most errors can be corrected by rechecking the Profile Parameter Table values. The

error is automatically cleared at powerup and at Program-to-Run Mode transitions.

Troubleshooting

If you’re having trouble with Mode 30 operation, please study the following

Guide for Mode 30

symptoms and possible causes. The most common problems are listed below:

Symptom: The stepper motor does not rotate.

Possible causes:

1. Configuration - Verify that the HSIO actually generates pulses on outputs

Y0 and Y1. Watch the status LEDs for Y0 and Y1 when you start a motion

profile. If the LEDs flicker on and off or are steadily on, the configuration is

probably correct.

2. Programming error - If there are no pulses on Y0 or Y1 you may have a

programming error. Check the contents of V2326 for an error code that may

be generated when the PLC attempts to do the move profile. Error code

descriptions are given above.

DL105 PLC User Manual, 2nd Edition, Rev. A

3-42

High-speed Input and Pulse Output Features

3. Wiring - Verify the wiring to the stepper motor is correct. Remember the

signal ground connection from the PLC to the motion system is required.

4. Motion system - Verify that the drive is powered and enabled. To verify the

motion system is working, you can use Mode 60 operation (normal PLC

inputs/outputs) as shown in the test program below. With it, you can

manually control Y0 and Y1 with X0 and X1, respectively. Using an input

simulator is ideal for this type of manual debugging. With the switches you

can single-step the motor in either direction. If the motor will not move with

this simple control, Mode 30 operation will not be possible until the problem

with the motor drive system or wiring is corrected.

DirectSOFT32

SP0

Load constant K60 into the accumulator. This

selects Mode 60 as the HSIO mode.

K60

Mode 60

Output the constant to V7633, the location of the

OUT

HSIO Mode select register.

V7633

Load the constant K1006 which is required to configure

Filtered Inputs

filtered inputs with a time constant of 10 mS.

K1006

Output this constant to V7634, configuring X0.

OUT

V7634

Output this constant to V7635, configuring X1.

OUT

V7635

Output this constant to V7636, configuring X2.

OUT

V7636

OUT

Use a switch on X0 input to manually control output Y0.

OUT

Use a switch on X1 input to manually control output Y1.

END

END coil marks the end of the main program..

5. Memory Error - HSIO configuration parameters are stored in the CPU

system memory. Corrupted data in this memory area can sometimes

interfere with proper HSIO operation. If all other corrective actions fail,

initializing the scratchpad memory may solve the problem. With

DirectSOFT32, select the PLC menu, then Setup, then Initialize

Scratchpad.

Symptom: The motor turns in the wrong direction.

Possible causes:

1. Wiring - If you have selected CW and CCW type operation, just swap the

wires on Y0 and Y1 outputs.

2. Direction control - If you have selected Pulse and Direction type

operation, just change the direction bit to the opposite state.

DL105 PLC User Manual, 2nd Edition, Rev. A

3-43

High-Speed Input and Pulse Output Features

Mode 40: High-Speed Interrupts

Purpose

The HSIO Mode 40 provides a high-speed interrupt to the ladder program. This

capability is provided for your choice of the following application scenarios:

S An external event needs to trigger an interrupt subroutine in the CPU.

Using immediate I/O instructions in the subroutine is typical.

S An interrupt routine needs to occur on a timed basis which is different

from the CPU scan time (either faster or slower). The timed interrupt is

programmable, from 5 to 999 mS.

Functional Block

The HSIO circuit creates the high-speed interrupt to the CPU. The following diagram

Diagram

shows the external interrupt option, which uses X0. In this configuration, X1, X2, and

X3 are all normal filtered inputs.

DL105

Output Circuit

PLC

Y0, Y1

Y2 - Y7

HSIO

I/O data

CPU

Interrupt

VĆmemory

Mode Select

V7633

xx40

FILTER

X1, X2, X3

X4- X11

Input Circuit

Alternately, you may configure the HSIO circuit to generate interrupts based on a

timer, as shown below. In this configuration, inputs X0 through X3 are filtered inputs.

DL105

Output Circuit

PLC

Y0, Y1

Y2 - Y7

HSIO

I/O data

CPU

Interrupt

VĆmemory

FILTER

Timer

Mode Select

V7633

xx40

X0, X1, X2, X3

X4- X11

Input Circuit

DL105 PLC User Manual, 2nd Edition, Rev. A

3-44

High-speed Input and Pulse Output Features

Recall that V7633 is the HSIO Mode Select register. Refer to the diagram below. Use

Setup for Mode 40

BCD 40 in the lower byte to select High-Speed Interrupt Mode. Use BCD 00 or 20 in

the upper byte as required. Combine the two bytes into a data word “xx40”, for writing

to V7633.

Memory Location V7633

Bits

Miscellaneous Setup (BCD)

HSIO Mode Setup (BCD)

00 = Power Up in Previous Mode

20 = Power Up in Run Mode Always

40 = High-Speed Interrupt

Choose the most convenient method of programming V7633 from the following:

S Include load and out instructions in your ladder program

S DirectSOFT32’s memory editor

S Use the Handheld Programmer D2-HPP

We recommend using the first method above so that the HSIO setup becomes an

integral part of your application program. An example program later in this section

shows how to to this.

Interrupts and the

Refer to the drawing below. The source of the interrupt may be external (X0), or the

Ladder Program

HSIO timer function. The setup parameter in V7634 serves a dual purpose:,

S It selects between the two interrupt sources, external (X0) or an internal

timer.

S In the case of the timer interrupt, it programs the interrupt timebase

between 5 and 999 mS.

The resulting interrupt uses label INT 0 in the ladder program. Be sure to include the

Enable Interrupt (ENI) instruction at the beginning of your program. Otherwise, the

interrupt routine will not be executed.

CPU Scan

Input

Update

Ladder

INT

Program

X0, External Interrupt

Execution

Interrupt

Routine

Program

current

TIMER

instruction

Interrupt source /

IRT

Time select

Input

Update

V7634

xxx4

DL105 PLC User Manual, 2nd Edition, Rev. A

3-45

High-Speed Input and Pulse Output Features

Signal pulses at X0 must meet certain timing criteria to guarantee an interrupt will

External Interrupt

result. Refer to the timing diagram below. The input characteristics of X0 are fixed (it

Timing Parameters

is not a programmable filtered input). The minimum pulse width is 0.1 mS. There

must be some delay before the next interrupt pulse arrives, such that the interrupt

period cannot be smaller than 0.5 mS.

0.5 mS minimum

0.1 mS minimum

External

Interrupt

Time

Timed Interrupt

When the timed interrupt is selected, the HSIO generates the interrupt to ladder

Parameters

logic. There is no interrupt “pulse width” in this case, but the interrupt period can be

adjusted from 5 to 999 mS.

5 mS to 999 mS

Timed

Interrupt

Time

X Input / Timed

The configurable discrete input options for High-Speed Interrupt Mode are listed in

the table below. Input X0 is the external interrupt when “0004” is in V7634. If you

INT Configuration

need a timed interrupt instead, then V7634 contains the interrupt time period, and

input X0 becomes a filtered input (uses X1’s filter time constant by default). Inputs

X1, X2, and X3 can only be filtered inputs, having individual configuration registers

and filter time constants. However, X0 will have the same filter time constant as X1

when the timed interrupt is selected.

Input

Configuration

Function

Hex Code

Required

V7634

External Interrupt

0004

Uses X1’s code

Filtered Input (when timed

0054 to 9994, which is

in V7635

interrupt is in use)

the timed INT timebase

V7635

Filtered Input

xx06 (xx = filter time)

V7636

Filtered Input

xx06 (xx = filter time)

V7637

Filtered Input

xx06 (xx = filter time)

DL105 PLC User Manual, 2nd Edition, Rev. A

3-46

High-speed Input and Pulse Output Features

External Interrupt

The following program selects Mode 40, then selects the external interrupt option.

Program Example

Inputs X1, X2, and X3 are all configured as filtered inputs with a 10 mS time constant.

The program is otherwise generic, and may be adapted to your application.

DirectSOFT32

SP0

Load constant K40 into the accumulator. This

selects Mode 40 as the HSIO mode.

K40

Mode 40

Output this constant to V7633, the location of the

OUT

HSIO Mode select register.

V7633

Load the constant K4 which is required to select the

External Interrupt

external interrupt option. X0 is the interrupt input.

Output this constant to V7634, configuring the

OUT

external interrupt option for X0.

V7634

Load the constant K1006 which is required to select

Filtered Inputs

filtered inputs with a 10 mS filter time constant.

K1006

Output this constant to V7635, configuring X1.

OUT

V7635

Output this constant to V7636, configuring X2.

OUT

V7636

Output this constant to V7637, configuring X3.

OUT

V7637

INT Enable

ENI

Enable Interrupts at the beginning of the program.

Main Program

Insert Main Program rungs here for your application.

END

END coil marks the end of the main program..

INT

The INT label marks the beginning of the interrupt

service routine program.

Interrupt Routine

Insert interrupt service routine rungs here for your

application.

IRT

Return to the main ladder program.

DL105 PLC User Manual, 2nd Edition, Rev. A

3-47

High-Speed Input and Pulse Output Features

Timed Interrupt

The following program selects Mode 40, then selects the timed interrupt option, with

Program Example

an interrupt period of 100 mS.

100 mS

Timed

Interrupt

Time

Inputs X0, X1, X2, and X3 are all configured as filtered inputs with a 10 mS time

constant. Note that X0 uses the time constant from X1. The program is otherwise

generic, and may be adapted to your application.

DirectSOFT32

SP0

Load constant K40 into the accumulator. This

selects Mode 40 as the HSIO mode.

K40

Mode 40

Output this constant to V7633, the location of the

OUT

HSIO Mode select register.

V7633

Load the constant K1004 which is required to select

Timed Interrupt

the timed interrrupt option, with a period of 100 mS.

K1004

Output this constant to V7634, configuring the timed

OUT

interrupt for 100 mS period.

V7634

Load the constant K1006 which is required to select

Filtered Inputs

filtered inputs with a 10 mS filter time constant.

K1006

Output this constant to V7635, configuring X1 and X0

OUT

V7635

Output this constant to V7636, configuring X2.

OUT

V7636

Output this constant to V7637, configuring X3.

OUT

V7637

INT Enable

ENI

Enable Interrupts at the beginning of the program.

Main Program

Insert Main Program rungs here for your application.

END

END coil marks the end of the main program..

INT

The INT label marks the beginning of the interrupt

service routine program.

Interrupt Routine

Insert interrupt service routine rungs here for your

application.

IRT

Return to the main ladder program.

DL105 PLC User Manual, 2nd Edition, Rev. A

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High-speed Input and Pulse Output Features

Mode 50: Pulse Catch Input

Purpose

The HSIO circuit has a pulse-catch mode of operation. It monitors the signal on input

X0, preserving the occurrence of a narrow pulse. The purpose of the pulse catch

mode is to enable the ladder program to “see” an input pulse which is shorter in

duration than the current scan time. The HSIO circuit latches the input event on input

X0 for one scan, and presents it to ladder logic through special relay SP100 contact.

This contact automatically goes off after one scan. Note that the ladder program

cannot read the status of X0 directly.

Functional Block

Refer to the block diagram below. When the lower byte of HSIO Mode register V7633

Diagram

contains a BCD “50”, the pulse catch mode in the HSIO circuit is enabled. X0

automatically becomes the pulse catch input, which sets the latch on each rising

edge. The HSIO resets the latch at the end of the next CPU scan. The latch output is

available to the ladder program through the special relay contact SP100. Inputs X1,

X2, and X3 are available as filtered discrete inputs.

DL105

Output Circuit

PLC

Y0, Y1

Y2 - Y7

HSIO

CPU

I/O data

LATCH

SP100

VĆmemory

Mode Select

Set Reset

FILTER

V7633

xx50

scan

X1, X2, X3

X4- X11

Input Circuit

Signal pulses at X0 must meet certain timing criteria to guarantee a pulse capture

Pulse Catch

will result. Refer to the timing diagram below. The input characteristics of X0 are

Timing Parameters

fixed (it is not a programmable filtered input). The minimum pulse width is 0.1 mS.

There must be some delay before the next pulse arrives, such that the pulse period

cannot be smaller than 0.5 mS. If the pulse period is smaller than 0.5 mS, the next

pulse will be considered part of the current pulse.

0.5 mS minimum

0.1 mS minimum

Pulse

Input

Time

Note that the pulse catch and filtered input functions are opposite in nature. The

pulse catch feature on X0 seeks to capture narrow pulses, while the filter input

feature on X1, X2, and X3 seeks to reject narrow pulses.

DL105 PLC User Manual, 2nd Edition, Rev. A

3-49

High-Speed Input and Pulse Output Features

Recall that V7633 is the HSIO Mode Select register. Refer to the diagram below. Use

Setup for Mode 50

BCD 50 in the lower byte to select High-Speed Counter Mode. Use BCD 00 or 20 in

the upper byte as required. Combine the two bytes into a data word “xx50”, for writing

to V7633.

Memory Location V7633

Bits

Miscellaneous Setup (BCD)

HSIO Mode Setup (BCD)

00 = Power Up in Previous Mode

20 = Power Up in Run Mode Always

50 = Pulse Catch Input

Choose the most convenient method of programming V7633 from the following:

S Include load and out instructions in your ladder program

S DirectSOFT32’s memory editor

S Use the Handheld Programmer D2-HPP

We recommend using the first method above so that the HSIO setup becomes an

integral part of your application program. An example program later in this section

shows how to to this.

X Input

The configurable discrete input options for Pulse Catch Mode are listed in the table

Configuration

below. Input X0 is the pulse input, and must have “0005” loaded into it configuration

own configuration register and filter time constant.

Input

Configuration

Function

Hex Code

Required

V7634

Pulse Catch Input

0005

V7635

Filtered Input

xx06 (xx = filter time)

V7636

Filtered Input

xx06 (xx = filter time)

V7637

Filtered Input

xx06 (xx = filter time)

DL105 PLC User Manual, 2nd Edition, Rev. A

DL105 Micro PLC. User Manual (2003) - page 3