Micromod MOD: Modcell 2050R MODBUS Communications - Manual (Page 41)

IB-23C650M
MODBUS PROTOCOL
Preset Single Register
Master Message Format Bytes
0 1 2 & 3 4 & 5 6 & 7
Device Address Function Code Register Number Register Data CRC
Slave Response (simple echo) Bytes
0 1 2 & 3 4 & 5 6 & 7
Device Address Function Code Register Number Register Data CRC
Loopback Diagnostic Test
Master Message Format Bytes
0 1 2 & 3 4 & 5 6 & 7
Device Address Function Code Diagnostic Code
(0000 only) Data (ignored) CRC
Slave Response (simple echo) Bytes
0 1 2 & 3 4 & 5 6 & 7
Device Address Function Code Diagnostic Code
(0000 only) Data (ignored) CRC
Force Multiple Coils
Master Message Format Bytes
0 1 2 & 3 4 & 5 6 7 ... x
x+1 &
x+2
Device
Address Function
Code Starting
Coil
Number Number
of Coils Number
of Data
Bytes Data Byte
1 ... Data
Byte n
CRC
Slave Response Bytes
0 1 2 & 3 4 & 5 6 & 7
Device Address Function Code Starting Coil Number Number of Coils CRC
37