Function Code 06: Store Single Setpoint; Function Code 07: Read Status - GE 735 Instruction Manual

4 MODBUS COMMUNICATIONS
Modbus Implementation: Preset Single Register
735/737 Implementation: Store Single Setpoint
This command allows the master to store a single setpoint into the memory of a slave device. The slave device response to
this function code is to echo the entire master transmission. Note that broadcast mode is not allowed with this function
code. When a broadcast transmission is sent by the master (that is, SLAVE ADDRESS = 0) the message will be ignored.
Message Format and Example:
Request slave 11 to store the value 039E in setpoint address 0049. After the transmission in this example is complete, set-
points address 0049 will contain the value 039E.
MASTER TRANSMISSION:
SLAVE ADDRESS
FUNCTION CODE
DATA STARTING ADDRESS
DATA
CRC
SLAVE RESPONSE:
SLAVE ADDRESS
FUNCTION CODE
DATA STARTING ADDRESS
DATA
CRC
Modbus Implementation: Read Exception Status
735/737 Implementation: Read General Status
This is a function used to quickly read the status of a selected relay. A short message length allows for rapid reading of sta-
tus. The status byte returned is the lower 8 bits of the relay status register defined in the memory map. Note that broadcast
mode is not allowed with this function code. The master transmission will be ignored by all slaves if broadcast mode is used
with this function code.
Message Format and Example:
Request status from slave 11. The status is stored in actual values memory map location 0014H. Assume the value is
01101101b.
MASTER TRANSMISSION:
SLAVE ADDRESS
FUNCTION CODE
CRC
SLAVE RESPONSE:
SLAVE ADDRESS
FUNCTION CODE
CODE VALUE
CRC
GE Power Management

4.2.5 FUNCTION CODE 06: STORE SINGLE SETPOINT

BYTES EXAMPLE / DESCRIPTION
1 11 message for slave 11
1 06 store single setpoint
2 00 49 setpoint address 0049h
2 03 9E data for address 0049h
2 ?? ?? CRC calculated by the master
BYTES EXAMPLE / DESCRIPTION
1 11 response message from slave 11
1 06 store single setpoint
2 00 49 setpoint address 0049h
2 03 9E data stored in 0049h
2 ?? ?? CRC calculated by the slave
BYTES EXAMPLE / DESCRIPTION
1 11 message for slave 11
1 07 read device status
2 ?? ?? CRC calculated by the master
BYTES EXAMPLE / DESCRIPTION
1 11 response message from slave 11
1 07 read device status
1 6D status = 001101101 (binary)
2 ?? ?? CRC calculated by the slave
735/737 Feeder Protection Relay
4.2 SUPPORTED MODBUS FUNCTIONS

4.2.6 FUNCTION CODE 07: READ STATUS

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