Yokogawa Standalone MW100 - Manual (Page 105)

App-3
IM MW100-17E
Appendix
1
2
3
App App
Index
Modbus Protocol Function Code
Slave Function/Server Function
The slave function of the main unit does not support broadcasted commands.
Function Code Function Operation
1 * Read statuses of coils (0xxxx) Reads statuses of a series of coils.
2 * Read statuses of input relays
(1xxxx)
Reads statuses of a series of input
relays.
3 Read values of hold registers
(4xxxx)
Reads values of a series of hold
registers.
4 Read values of Input registers
(3xxxx)
Reads values of a series of input
registers.
5 * Turn status of a single coil (0xxxx) Turns status of a single coil.
6 Write a value to a single hold
register (4xxxx)
Writes a value to a hold register.
8 Loop back test Returns the same message as the
command message.
15 * Turn statuses of coils (0xxxx) Turns statuses of a series of coils.
16 Write values to hold registers
(4xxxx)
Writes values to a series of hold
registers.
* Firmware version R3.03 or later
Master Function/Client Function
Function Code Function Action
1 * Read statuses of coils (0xxxx) Reads statuses of a series of coils.
2 * Read statuses of input relays
(1xxxx)
Reads statuses of a series of input
relays.
3 Read values of hold registers
(4xxxx, 4xxxxx)
Reads values of a series of hold
registers.
4 Read values of Input registers
(3xxxx, 3xxxxx)
Reads values of a series of input
registers.
5 * Turn status of a single coil (0xxxx) Turns off/on a single coil.
6 Write a value to a single hold
register
(4xxxx, 4xxxxx)
Writes a value to a hold register.
15 * Turn statuses of coils (0xxxx) Turns off/on a series of coils.
16 Write values to hold registers
(4xxxx ,4xxxxx)
Writes values to a series of hold
registers.
* Firmware version R3.04 or later
Bit data values output by Modbus client/master when the command type is set to “Write”
in the Modbus client/master settings, see the followings:
• Values per Modbus Registers (Measurement channel data and MATH channel
data)(page App-7)
• Values per Modbus Registers (Communication input channel data)(page App-8)
Appendix 2 Modbus Protocol