ABB Zenith 50P-2035 Operation And Maintenance Manual page 23

Appendix G
Modbus Protocol Illustration
Response
The response from the slave is an echo of the slave
address, function code, starting address and number
of coils forced.
Starting Starting
Slave Function
Address Address
Address Code
High Order Low Order
09h 0Fh 00h
Figure G10 – Write Multiple Coils Response Message
Write Multiple Holding Registers (Function Code 16)
Presets values into a sequence of holding registers.
Query
The following is an example to preset two registers
starting at 40034 ( W -Time) to 9 hex (9 seconds) and 40035
( W 3-time) to 32 hex (50 seconds), in slave device 17.
Starting Starting Number Number
Slave Function Address Address of Regs of Regs
Address Code High Low High Low
Order Order Order Order
11h 10h 00h 21h 00h 02h
Figure G11 – Write Multiple Registers Query Message
ABB Zenith
I
(cont'd)
Number Number Error
of Coils of Coils Check Field
High Low ( LRC or
Order Order
CRC
28h 00h 10h —
Error
Data Data Data Data
Check
Byte
High Low High Low Field
Count
( LRC or
Order Order Order Order
CRC
04h 00h 09h 00h 32h
MX150/MX250 Series Modbus Network Card (71R-2200)
(cont'd)
Response
The response from the slave is an echo of the slave
address, function code, starting address and number
of registers to be loaded.
Starting
Slave Function Address
Address Code
)
Order
11h 10h
Figure G12 – Write Multiple Registers Response Message
)
–
Starting Number Number
Address of Regs of Regs
High Low High Low
Order Order Order
00h 21h 00h 02h
Error
Check Field
( LRC or
CRC )
—
21
I