
8–10
MM3 MOTOR MANAGER 3 – INSTRUCTION MANUAL
SUPPORTED MODBUS FUNCTIONS
CHAPTER 8: COMMUNICATIONS
8.2.8
Function Code
08h
Modbus implementation: Loopback test
MM3 Motor Manager 3 implementation: Loopback test
This function is used to test the integrity of the communication link. The MM3 Motor
Manager 3 will echo the request. For example, consider a loopback test from slave 17:
8.2.9
Function Code
10h
Modbus implementation: Preset multiple registers
MM3 Motor Manager 3 implementation: Store multiple setpoints
This function code allows multiple setpoints to be stored into the MM3 Motor Manager 3
memory. Modbus registers are 16-bit (two byte) values transmitted high order byte first.
Thus all MM3 Motor Manager 3 setpoints are sent as two bytes. The maximum number of
setpoints that can be stored in one transmission is dependent on the slave device. Modbus
allows up to a maximum of 60 holding registers to be stored. The MM3 Motor Manager 3
response to this function code is to echo the slave address, function code, starting address,
the number of Setpoints stored, and the CRC.
For example, consider a request for slave 17 to store the value 01F4 to setpoint address
1028 and the value 2710 to setpoint address 1029.
The master/slave packets have the following format:
Master Transmission
Bytes
Example
Description
Slave address
1
11
message for slave 17
Function code
1
08
loopback test
Diagnostic code
2
00 00
must be 0000h
Data
2
00 00
must be 0000h
CRC
2
E0 0B
computed CRC error code
Slave Response
Bytes
Example
Description
Slave address
1
11
message from slave 17
Function code
1
08
loopback test
Diagnostic code
2
00 00
must be 0000h
Data
2
00 00
must be 0000h
CRC
2
E0 0B
computed CRC error code
Master Transmission
Bytes
Example
Description
Slave address
1
11
message for slave 17
Function code
1
10
store multiple setpoints
Data starting address
2
10 28
setpoint address 1028h
Number of setpoints
2
00 02
2 setpoints = 4 bytes total
Byte count
1
04
4 bytes of data
Data word 1
2
01 F4
data for address 1028h
Data word 2
2
27 10
data for address 1029h
CRC
2
33 23
computed CRC error code
Slave Response
Bytes
Example
Description
Slave address
1
11
message from slave 17
Function code
1
10
store multiple setpoints
Data starting address
2
10 28
setpoint address 1028h
Содержание MM3
Страница 8: ...vi MM3 MOTOR MANAGER 3 INSTRUCTION MANUAL TABLE OF CONTENTS ...
Страница 11: ...CHAPTER 1 INTRODUCTION OVERVIEW MM3 MOTOR MANAGER 3 INSTRUCTION MANUAL 1 3 Figure 1 1 Functional block diagram ...
Страница 18: ...1 10 MM3 MOTOR MANAGER 3 INSTRUCTION MANUAL TECHNICAL SPECIFICATIONS CHAPTER 1 INTRODUCTION ...
Страница 80: ...4 18 MM3 MOTOR MANAGER 3 INSTRUCTION MANUAL CHASSIS MOUNT UNITS CHAPTER 4 SOFTWARE ...
Страница 124: ...5 44 MM3 MOTOR MANAGER 3 INSTRUCTION MANUAL S7 TESTING CHAPTER 5 SETPOINTS ...
Страница 198: ...8 54 MM3 MOTOR MANAGER 3 INSTRUCTION MANUAL MODBUS MEMORY MAP CHAPTER 8 COMMUNICATIONS ...
Страница 220: ...10 14 MM3 MOTOR MANAGER 3 INSTRUCTION MANUAL GE MULTILIN WARRANTY CHAPTER 10 MISCELLANEOUS ...