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24.13

SVCREQ 10: Read Folder Name

Use SVCREQ 10 to read the name of the currently executing folder.

24.13.1

Output Parameter Block Format for SVCREQ 10

The output parameter block has a length of four words.  It returns eight ASCII characters;
the last is a null character (00h).  If the program name has fewer than seven characters, null
characters are added to the end.

Low Byte

High Byte

address

character 1

character 2

address + 1

character 3

character 4

address + 2

character 5

character 6

address + 3

character 7

Example of SVCREQ 10

In this example, when enabling input %I0301 goes OFF, register location %R0099 is loaded
with the value 10, which is the function code for the Read Folder Name function. The
Program Block READ_ID is then called to retrieve the folder name. The parameter block is
located at address %R0100.

Figure 357

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24.14

SVCREQ 11: Read PLC ID

Use SVCREQ 11 to read the name of the PLC executing the program.

24.14.1

Output Parameter Block Format for SVCREQ 11

The output parameter block has a length of four words. It returns eight ASCII characters;
the last is a null character (00h). If the PLC ID has fewer than seven characters, null characters
are added to the end.

Low Byte

High Byte

address

character 1

character 2

address + 1

character 3

character 4

address + 2

character 5

character 6

address + 3

character 7

Example of SVCREQ 11

In this example, when enabling input %I0302 goes OFF, register location %R0099 is loaded
with the value 11, which is the function code for the Read PLC ID function. The program
block READ_ID is then called to retrieve the ID. The parameter block is located at address
%R0100.

Figure 358

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24.15

SVCREQ 13: Shut Down (Stop) PLC

Use SVCREQ 13 to stop the Micro PLC at the end of the next sweep. All outputs go to the

OFF state at the start of the next PLC sweep. An informational “Shut Down PLC” fault

placed in the PLC Fault Table. The I/O scan continues as configured.

24.15.1

Parameter Block for SVCREQ 13

This function has no parameter block.

Example of SVCREQ 13

In the example, when %T0001 is set SVCREQ 13 executes. The PARM input is not used.

This example uses a JUMP to the end of the program to force a shutdown if the Shutdown
PLC function executes successfully. This JUMP and LABEL are needed because the transition
to Stop mode does not occur until the end of the sweep in which the function executes.

Figure 359

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24.16

SVCREQ 14: Clear Fault

Use SVCREQ 14 to clear either the PLC fault table or the I/O fault table. The SVCREQ output
is set ON unless some number other than 0 or 1 is entered as the requested operation.

24.16.1

Input Parameter Block for SVCREQ 14

For this function, the parameter block has a length of 1 word. It is an input parameter block
only. There is no output parameter block.

0 = clear PLC fault table.
1 = clear I/O fault table.

Example of SVCREQ 14

In  the  example,  when  input  %I0346  is  on  and  input  %I0349  is  on,  the  PLC  fault  table  is
cleared.  When input %I0347 is on and input %I0349 is on, the I/O fault table is cleared.  When
input %I0348 is on and input %I0349 is on, both are cleared.  A positive transition coil should
be used to trigger SVCREQ14.

The parameter block for the PLC fault table is located at %R0500; for the I/O fault table the
parameter block is located at %R0550. Both parameter blocks are set up elsewhere in the
program.

Figure 360

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24.17

SVCREQ 15: Read Last-Logged Fault Table
Entry

Use SVCREQ 15 to read the last entry logged in either the PLC fault table or the I/O fault
table. The SVCREQ output is set ON unless some number other than 0 or 1 is entered as the
requested operation or the fault table is empty.

24.17.1

Input Parameter Block for SVCREQ 15

For this function, the parameter block has a length of 22 words. The input parameter block
has this format:

2-Digit Year Format

4-Digit Year Format

address

0 = Read PLC fault table.

8 = Read PLC fault table.

1 = Read I/O fault table.

9 = Read I/O fault table.

The format of the output parameter block depends on whether the function reads data from
the PLC fault table or the I/O fault table.

PLC Fault Table Output Format

I/O Fault Table Output Format

High Byte

Low Byte

High Byte

Low Byte

spare

long/short

address + 1

memory type

long/short

spare

address + 2

offset

slot

rack

address + 3

slot

rack

task

address + 4

block

bus

fault action

fault group

address + 5

point

error code

address + 6

fault action

fault group

fault specific data

address + 7

fault type

fault category

address + 8

fault specific data

fault description

address + 18

minutes

seconds

address + 19

minutes

seconds

day of month

hour

address + 20

day of month

hour

2-Digit Year
Format

year

month

address + 21

year

month

4-Digit Year spare

month

address + 21

spare

month

Format

year

address + 22

year

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Long/Short Value

The first byte of word address +1 contains a number that indicates the length of the fault-
specific data in the fault entry. These possible values are:

PLC fault table

00 = 8 bytes (short)
01 = 24 bytes (long)

I/O fault table

02 = 5 bytes (short)
03 = 21 bytes (long)

Example of SVCREQ 15

When inputs %I0250 and %I0251 are both on, the first Move function places a zero (read PLC
fault table) into the parameter block for SVCREQ 15. When input %I0250 is on and input
%I0251 is off, the Move instruction instead places a one (read I/O fault table) in the SVCREQ
parameter block. The parameter block is located at location %R0600.

Figure 361

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24.18

SVCREQ 16: Read Elapsed Time Clock

Use SVCREQ 16 to read the system's elapsed time clock. The elapsed time clock measures
the time in seconds since the Micro PLC was powered on.

24.18.1

Output Parameter Block for SVCREQ 16

This function has an output parameter block only. Its length is 3 words.

address

seconds from power on (low order)

address + 1

seconds from power on (high order)

address + 2

100 µs ticks

The first two words are the elapsed time in seconds. The last word is the number of 100 µs
ticks in the current second.

Example of SVCREQ 16

In the example, when internal coil %M0233 is on, the SVCREQ with a parameter block
located at %R0127 reads the system's elapsed time clock and sets internal coil %M0234.
When coil %M0233 is off, the SVCREQ with a parameter block at %R0131 reads the elapsed
time clock again.

The subtraction function finds the difference between the first and second readings, which
have been stored in the SVCREQ parameter blocks. The subtraction ignores the hundred
microsecond ticks.

The difference between the two readings is placed in memory location %R0250.

Figure 362

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24.19

SVCREQ 18: Read I/O Override Status

Use SVCREQ 18 to check for any overrides in the Micro PLC 's %I and %Q memories.

24.19.1

Output Parameter Block for SVCREQ 18

This function has an output parameter block only. Its length is 1 word.

address

0 = No overrides are set.

1 = Overrides are set.

Example of SVCREQ 18

The following SVCREQ reads the status of I/O overrides memory into location %R1003. The
equality function checks %R1003 to see if it is equal to (the constant) 1. If it is, the equality
function turns on output %T0001.

Figure 363

24.20

SVCREQ 23: Read Master Checksum

Use SVCREQ 23 to read the master checksums of the application program and the
configuration. The SVCREQ output is always ON if the function is enabled.

24.20.1

Output Parameter Block for SVCREQ 23

For this function, the output parameter block has a length of 12 words with this format:

The first two items in the output parameter block indicate when the program and
configuration checksums are valid. (Program checksums may not be valid during a Run
Mode Store.)

address

Master Program Checksum Valid (0 = not valid, 1 = valid)

address + 1

Master Configuration Checksum Valid (0 = not valid, 1 = valid)

address + 2

Number of Program Blocks (including _MAIN)

address + 3

Size of User Program in Bytes (DWORD data type)

address + 5

Program Additive Checksum

address + 6

Program CRC Checksum (DWORD data type)

address + 8

Size of Configuration Data in Bytes

address + 9

Configuration Additive Checksum

address + 10

Configuration CRC Checksum (DWORD data type)

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Example of SVCREQ 23

In the example, when input %I0251 is ON, the master checksum information is placed into
the parameter block at %R0050 and the output coil (%Q0001) is turned on.

Figure 364

24.21

SVCREQ 26/ SVCREQ 30: Interrogate I/O

Use SVCREQ 26 and SVCREQ30 to check whether the installed modules match the software
configuration. If not, these SVCREQs place appropriate addition, loss, and mismatch faults
in the PLC and/or I/O fault tables. SVCREQ 26 and SVCREQ 30 both perform the same
function.

The more configuration faults there are, the longer it takes these SVCREQs longer to
execute.

These SVCREQs have no parameter block. They always output power flow.

Example of SVCREQ 26

In the example, when input %I0251 is ON, the SVCREQ checks the installed modules and
compares them to the software configuration. Output %Q0001 is turned on after the
SVCREQ is complete.

Figure 365

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24.22

SVCREQ 29: Read Elapsed Power Down Time

Use SVCREQ 29 to read the amount of time elapsed between the last power-down and the
most recent power-up. If the watchdog timer expired before power-down, the PLC is not
able to calculate the power down elapsed time, so the time is set to 0.

The SVCREQ output is always ON.

24.22.1

Output Parameter Block for SVCREQ 29

This function has an output parameter block only. The parameter block has a length of 3
words.

address

Power-Down Elapsed Seconds (low order)

address + 1

Power-Down Elapsed Seconds (high order)

address + 2

zero

The first two words are the power-down elapsed time in seconds. The last word is always 0.

Example of SVCREQ 29

In the example, when input %I0251 is ON, the Elapsed Power-Down Time is placed into the
parameter block that starts at %R0050. The output coil (%Q0001) is turned on.

Figure 366

24.23

SVCREQ 34: Enter Analog Calibration Mode

The final step of calibrating an analog channel (see the complete process description in
Chapter 5:) consists of storing the calibration values in flash memory. This step requires the
use of two SVCREQ functions, SVCREQ 34 and 35.

SVCREQ 34 places the Micro PLC in calibration mode. When SVCREQ 34 is executed, the PLC
uses default gain and offset so that you can start the calibration process. No parameter
block is needed with SVCREQ 34.

Note:

This calibration procedure applies to analog channels on 23-point Micro PLCs only. Software
calibration of Analog Expansions and Nano PLCs is not available.

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Example of SVCREQ 34

In the following example, when enabling input %I0251 goes ON, the analog calibration
defaults are restored and output coil %Q0001 is turned on.

Figure 367

24.24

SVCREQ 35: Store Analog Calibration

SVCREQ 35 stores the previously computed analog calibration in the Micro PLC. The
calibration can be stored in either volatile or non-volatile memory.

SVCREQ 35 uses an input parameter block containing the new calibration data and control
data. Contents of the parameter block are shown on the next page. When the SVCREQ is
successfully completed, the new calibration values take effect.

After the SVCREQ function executes, the PLC returns the function status and the number of
tries available to the 2 words of the output parameter block.

Example of SVCREQ 35

In the example, when contact %I0003 is on, the SVCREQ with a parameter block located at
%R0127 stores the analog calibration to the memory type specified in the parameter block
and sets coil %Q00234.

Figure 368

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24.24.1

Input Parameter Block for SVCREQ 35

The input parameter block for SVCREQ 35 contains the following 32 input words. For
parameter explanations, refer to Parameter Definitions below.

Address

Password (“CA” 4143H)

address + 1

Password (“LB” 424CH)

address + 2

Destination Control: 0 for RAM, 1 for flash

address + 3

Select Control AI Ch 1 Vol: 0: last, 1: new, 2: default, 3: factory

address + 4

Input Channel 1 %AI0018 High Value, Voltage

address + 5

Input Channel 1 %AI0018 Low Value, Voltage

address + 6

Input Channel 1 Meter High Value, Voltage (mV)

address + 7

Input Channel 1 Meter Low Value, Voltage (mV)

address + 8

Select Control AI Ch 1 Cur: 0: last, 1: new, 2: default, 3: factory

address + 9

Input Channel 1 %AI0018 High Value, Current

address + 10

Input Channel 1 %AI0018 Low Value, Current

address + 11

Input Channel 1 Meter High Value, Current (mA)

address + 12

Input Channel 1 Meter Low Value, Current (mA)

address + 13

Select Control AI Ch 2 Vol: 0: last, 1: new, 2: default, 3: factory

address + 14

Input Channel 2 %AI0019 High Value, Voltage

address + 15

Input Channel 2 %AI0019 Low Value, Voltage

address + 16

Input Channel 2-Meter-High Value, Voltage (mV)

address + 17

Input Channel 2 Meter Low Value, Voltage (mV)

address + 18

Select Control AI Ch 2 Cur: 0: last, 1: new, 2: default, 3: factory

address + 19

Input Channel 2 %AI0019 High Value, Current

address + 20

Input Channel 2 %AI0019 Low Value, Current

address + 21

Input Channel 2-Meter-High Value, Current (mA)

address + 22

Input Channel 2 Meter Low Value, Current (mA)

address + 23

Select Control AQ Ch 1 Vol: 0: last, 1: new, 2: default, 3: factory

address + 24

Output Channel 1 %AQ0012 High Value, Voltage

address + 25

Output Channel 1 %AQ0012 Low Value, Voltage

address + 26

Output Channel 1 Meter High Value, Voltage (mV)

address + 27

Output Channel 1 Meter Low Value, Voltage (mV)

address + 28

Select Control AQ Ch 1 Cur: 0: last, 1: new, 2: default, 3: factory

address + 29

Output Channel 1 %AQ0012 High Value, Current

address + 30

Output Channel 1 %AQ0012 Low Value, Current

address + 31

Output Channel 1 Meter High Value, Current (mA)

address + 32

Output Channel 1 Meter Low Value, Current (mA)

address + 33

Status

address + 34

Number of tries available

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24.24.2

Output Parameter Block for SVCREQ 35

The output parameter block for SVCREQ 35 contains the following two output words:

address

Status

address + 1

Number of tries available

Parameter Definitions

Password (address and address +1) must be CALB. If an invalid password is provided, the
service request returns error 3 in the status word.

Destination Control (at address +2), determines whether to write the constants in flash or
in RAM. You can select the RAM option (0) and calibrate as many times as necessary without
burning the calibration constants into the flash memory. When you are satisfied with the
calibration, you can select the flash option (1) and finalize the calibration. When the flash
option is selected, the calibration data is copied into RAM as well as burned into flash
memory. It is important to issue a SVCREQ with the flash option selected in the Destination
Control parameter field once the desired calibration state is reached. Otherwise, the new
calibration values will be lost when the unit is powered off.

Select Control (address +3). Allows you to calibrate a particular channel in a specific mode.
Four choices are allowed for each channel:

Last user calibration. The last calibration in flash is used for the channel and for the mode. (If
no user calibration exists, the last factory calibration is used.)

New. The PLC calculates new gain and offset using the values supplied in the next four words.
New calibration value will replace the value in the RAM or flash as determined by the
Destination Control field.

Default. If this option is specified, the default calibration value is used.

Factory. If this option is specified, the last factory calibration value is used.

Status (address +33). A status word is returned by the service request:

1=Complete

4=Not in calibration mode

2=Out of tries

5=Calibration values checksum bad

3=Invalid password 6=Invalid calibration data

Number of Tries Available (address +34). Indicates the number of tries remaining.

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24.25

SVCREQ 52: Read from Flash

This Service Request is available with Release 3.0 and later Micro PLCs.

Service Request 52 reads Reference Variables that were previously written into flash
memory using Service Request 53 and stores the variables in CPU reference memory. Each
execution of Service Request 52 can read:

•

1 to 10 words of %R, %AI, or %AQ reference data.

•

1 to 10 bytes of %I, %Q, %M, %T, or %G reference data.

SVCREQ 52 uses an input parameter block containing the reference memory to be read.
After SVCREQ 52 executes, the PLC returns the function status to the two words of the
output parameter block.

Example of SVCREQ 52

In this example, when enabling input %M0003 goes on, the Service Request reads the flash
memory location specified in the Parameter Block located at %R00040 and places the data
into the intended destination. It then sets coil %M0004.

Figure 369

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24.25.1

Input Parameter Block for SVCREQ 52

The input parameter block for SVCREQ 52 contains the following 5 input words.

Address

Memory type (number) of the flash memory location of the first byte or word of data
to be read. Numbers are:

Memory

Decimal

Hex

%I (byte)

%Q (byte)

%T (byte)

%M (byte)

%G (byte)

%R (word)

%AI (word)

%AQ (word)

address + 1 Offset of the requested data within the memory type in flash memory

address + 2 Length of data to be read, 1

–

10 bytes or words.

address + 3 Memory type of the PLC reference memory type where the requested data should be

placed. See the numbers above.

address + 4 Offset to place the requested data within the requested memory type in PLC reference

memory.

address + 5 Memory type of the PLC reference memory type for the completion status.

See the numbers above. For example, %R1 = memory type 8.

address + 6 Offset in PLC Memory to write completion status (zero based).

For example, %R1 = offset 0.

24.25.2

Status Data for SVCREQ 52

SVCREQ 52 returns one of the following status indications:

Word 0

Hex

Dec Status

Definition

0x0001

Full Success

All requested data was successfully read

0x0101

257

Partial Success

Less than requested data length was read. Can occur
if all data requested was not present in flash.

0x0102

258

Insufficient Dest Mem Can occur if the PLC reference memory location

specified is not sufficient to store all the data read
from flash

0x0202

514

Invalid Length

Length is beyond minimum 1 and maximum 10

0x0302

770

Source/Dest
Mem Wrong

Wrong source or destination reference memory
specified in the SVCREQ.

Word 1

Number of bytes read

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24.26

SVCREQ 53: Write to Flash

This Service Request is available with Release 3.0 and later Micro PLCs.

Service Request 53 stores requested PLC reference data in flash memory. Each execution of
Service Request 53 can write:

•

1 to 10 words of %R, %AI, or %AQ reference data.

•

1 to 10 bytes of %I, %Q, %M, %T, or %G reference data.

SVCREQ 53 uses an input parameter block containing the reference memory requested to
be written. After SVCREQ 53 executes, the PLC returns the function status and the amount
of user flash memory still available to the output parameter block.

Example of SVCREQ 53

In the example, when enabling input %M0003 goes on, the Service Request reads the PLC
memory location specified in the Parameter Block located at %R00040 and writes the data
to flash. It then sets coil %M0004.

Figure 370

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