Performing Commands Using Function Code 10H - GE 350 Communications Manual

CHAPTER 8: MODBUS FUNCTIONS

Performing Commands Using Function Code 10H

SR3 SERIES PROTECTIVE RELAY PLATFORM – COMMUNICATIONS GUIDE
Field Name
Slave Address
Function
Starting Address Hi
Starting Address Lo
No. of Registers Hi
No. of Registers Lo
Commands can be performed using function code 16 (10H) as well as function code 5.
When using FUNCTION CODE 16, the Command Function register must be written with a
value of 5. The Command Operation register must be written with a valid command
operation number. The Command Data registers must be written with valid data; this is
dependent upon the command operation.
For example, consider a request for slave 17 to perform command operation 1 (RESET): The
master/slave packets have the following format:
Table 8-9: MASTER/SLAVE PACKET FORMAT FOR PERFORMING COMMANDS
MASTER TRANSMISSION
SLAVE ADDRESS
FUNCTION CODE
DATA STARTING ADDRESS
NUMBER OF SETPOINTS
BYTE COUNT
DATA 1
DATA 2
CRC
SLAVE RESPONSE
SLAVE ADDRESS
FUNCTION CODE
DATA STARTING ADDRESS
NUMBER OF SETPOINTS
CRC
Hex
FE
10
0F
0A
00
02
BYTES EXAMPLE
1 11
1 10
2 00 80
2 00 02
1 04
2 00 05
2 00 01
2 7E CE
BYTES EXAMPLE
1 11
1 10
2 00 80
2 00 02
2 42 B0
FUNCTION CODE 10H
DESCRIPTION
message for slave 17
store multiple
setpoints
setpoint address 00
80
2 setpoints = 4 bytes
total
4 bytes of data
data for address 00
80
data for address 00
81
CRC error code
DESCRIPTION
message from slave
17
store multiple
setpoints
setpoint address 00
80
2 setpoints
CRC error code
8-13