Description of Modicon M580-specific System Words %SW128 to %SW167
Original instructions
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Detailed Description
Description of system words %SW128 to %SW141:
Word
Symbol
%SW132 to %SW134
Function
MAC address
Initial State
0
These words contain the following data:
  • %SW132: the MAC address - high bytes
  • %SW133: the MAC address - middle bytes
  • %SW134: the MAC address - low bytes
Example @MAC = AA-BB-CC-DD-EE-FF
  • %SW132 = AABB hex
  • %SW133 = CCDD hex
  • %SW134 = EEFF hex
%SW135 to %SW137
Function
Serial number
Initial State
0
These words contain the serial number of the M580 PLC (correspond to the S/N written on the module itself):
  • %SW135: the Serial Number - high bytes
  • %SW136: the Serial Number - middle bytes
  • %SW137: the Serial Number - low bytes
Example: SN21143512345
  • %SW135: 21 - factory code
  • %SW136: 1435 - year(14) and week(35)
  • %SW137: 12345 - forder number (on 5 digit)
%SW139 and %SW141
Function
Modbus objects base
Initial State
–
Base addresses for %M (coil address) and %MW (holding register)
The base address is the number of %M or %MW which corresponds to Modbus address 0000.
WARNING
UNINTENDED EQUIPMENT OPERATION
You must set the values of the 2 system words %SW139 and %SW141 using the “Initial value” mechanism.
Do not use programming code to set the values.
Otherwise, when using the PLC init command or setting %S0 to 1 or downloading an application, the 2 system words are set to 0000 and the behavior of Modbus server is wrong.
Failure to follow these instructions can result in death, serious injury, or equipment damage.
Description of system words %SW146 to %SW167:
Word
Symbol
%SW146 and %SW147
Function
SD card serial number
Initial State
0
Those 2 system words contain the unique SD card serial number (32bits).
If there is not an SD card or an unrecognized SD card, the 2 system words are set to 0.
This information can be used to protect an application against duplication.
%SW148
Function
ECC error counter
Initial State
0
This word contains the number of bits in error in DDR, detected and fixed by the ECC.
%SW150
Function
Management of Error Correcting Code (ECC)
Initial State
0
Used to enable/disable ECC:
  • To disable ECC: write the value 16#DECC to %SW150.
    NOTE: Because ECC is enabled by default, you will need to re-write the value 16#DECC to %SW150 after a cold start, caused either by pressing the RESET button or by application logic.
  • To enable ECC: write an value other than 16#DECC to %SW150, cycle power to the CPU, or press the RESET button.
NOTE:
  • The status of ECC is displayed in %S109.
  • %SW150 is valid only for M580 redundant CPUs (BMEH58xxxx) with firmware version 2.50 and higher. %SW150 has no effect on standalone CPUs.
  • In a redundant CPU system, the value of %SW150 is transferred from the primary to the standby PAC.
%SW151
Function
Multiple ECC error counter
Initial State
0
This counter is incremented each time a multiple ECC error occurs.
%SW151 is valid only for M580 CPUs with firmware version 2.50 and higher.
This counter cannot be reset.
%SW160 to %SW167
PREMRACK0 to PREMRACK7
Function
Detected errors for racks 0 to 7
Initial State
–
Words %SW160 to %SW167 are associated, respectively, to racks 0 to 7.
Bits 0 to 15 of each of these words are associated with the modules located in positions 0 to 15 of these racks.
The bit is at 0 if the module has a detected error, and at 1 if the module is operating correctly.
Example: %SW163.5 = 0, the module located in position 5 on rack 3 has a detected error.
In case of half racks, 2 contiguous half racks make a complete normal rack, referenced by only one %SWi.
%SW171
Function
Fast task state indication
Initial State
–
State of the FAST task:
  • 0: No FAST task exists
  • 1: Stop
  • 2: Run (all process tasks are in the Run state)
  • 3: Breakpoint
  • 4: Halt
%SW173
Function
MAST task state indication
Initial State
–
State of the MAST task:
  • 0: No MAST task exists
  • 1: Stop
  • 2: Run
  • 3: Breakpoint
  • 4: Halt
%SW174
Function
AUX0 task state indication
Initial State
–
NOTE: Only for standalone PLC.
State of the AUX0 task:
  • 0: No AUX0 task exists
  • 1: Stop
  • 2: Run
  • 3: Breakpoint
  • 4: Halt
%SW175
Function
AUX1 task state indication
Initial State
–
NOTE: Only for standalone PLC.
State of the AUX1 task:
  • 0: No AUX1 task exists
  • 1: Stop
  • 2: Run
  • 3: Breakpoint
  • 4: Halt