3 function code 05: execute operation, 4 function code 06: store single setpoint, Function code 05: execute operation -4 – GE 489 User Manual
Page 166: Function code 06: store single setpoint -4
6-4
489 Generator Management Relay
GE Multilin
6.2 MODBUS FUNCTIONS
6 COMMUNICATIONS
6
6.2.3 FUNCTION CODE 05: EXECUTE OPERATION
Modbus Implementation: Force Single Coil
489 Implementation:
Execute Operation
This function code allows the master to request specific 489 command operations. The command numbers listed in the
Commands area of the memory map correspond to operation code for function code 05. The operation commands can also
be initiated by writing to the Commands area of the memory map using function code 16. Refer to Section 6.2.7 Function
Code 16: Store Multiple Setpoints on page 6–6 for complete details.
Supported Operations:
Reset 489 (operation code 1); Generator Start (operation code 2);
Generator Stop (operation code 3); Waveform Trigger (operation code 4)
MESSAGE FORMAT AND EXAMPLE
Reset 489 (operation code 1).
6.2.4 FUNCTION CODE 06: STORE SINGLE SETPOINT
Modbus Implementation: Preset Single Register
489 Implementation:
Store Single Setpoint
This command allows the master to store a single setpoint into the 489 memory. The slave response to this function code is
to echo the entire master transmission.
MESSAGE FORMAT AND EXAMPLE
Request slave 11 to store the value 01F4 in Setpoint address 1180. After the transmission in this example is complete, Set-
points address 1180 will contain the value 01F4.
MASTER TRANSMISSION:
BYTES
EXAMPLE (HEX):
SLAVE ADDRESS
1
0B
message for slave 11
FUNCTION CODE
1
05
execute operation
OPERATION CODE
2
00 01
reset command (operation code 1)
CODE VALUE
2
FF 00
perform function
CRC
2
DD 50
CRC calculated by the master
SLAVE RESPONSE:
BYTES
EXAMPLE (HEX):
SLAVE ADDRESS
1
0B
response message from slave 11
FUNCTION CODE
1
05
execute operation
OPERATION CODE
2
00 01
reset command (operation code 1)
CODE VALUE
2
FF 00
perform function
CRC
2
DD 50
CRC calculated by the slave
MASTER TRANSMISSION:
BYTES
EXAMPLE (HEX):
SLAVE ADDRESS
1
0B
message for slave 11
FUNCTION CODE
1
06
store single setpoint
DATA STARTING ADDRESS
2
11 80
setpoint address 1180
DATA
2
01 F4
data for address 1180
CRC
2
8D A3
CRC calculated by the master
SLAVE RESPONSE:
EXAMPLE (HEX):
SLAVE ADDRESS
1
0B
message for slave 11
FUNCTION CODE
1
06
store single setpoint
DATA STARTING ADDRESS
2
11 80
setpoint address 1180
DATA
2
01 F4
data for address 1180
CRC
2
8D A3
CRC calculated by the slave