Ebyte E831-RTU(8080T-485) User Manual page 17

Function code：01，Read coil status
Address range : 00017(0x0010)~00023(0x0017)
Example：
Read 8 digital output status. Assuming the return value is 03, the corresponding binary bit is 0000
0011, which means that DO1 and DO2 are on. The 8 bits represent digital output status, which are DO8,
DO7, DO6, DO5, DO4, DO3, DO2, DO1 in order.
Modbus RTU protocol read digital output:
01
Transmis
Device ModBus
sion
Address
01
Receivin
Device ModBus
g
Address
4.2.1.2. Control switch value DO output
Function code：05，Write single coil status; 0F, write multiple coil status
Address range：00017(0x0010)~00023(0x0017)
Example：
Function code 0x05 writes DO2 digital output, the write value is FF 00; close D02 port, write the
value 00 00.
Modbus RTU protocol write digital output：
01
Transmis
Device ModBus
sion
Address
01
Receivin
Device ModBus
g
Address
Function code 0x0F writes DO2 and DO3 digital output. The write value should be 0x03,
corresponding to the binary bit 0000 0011. (Note that the initial address here starts from DO2.)
01 00 10
Function Switch value
code initial address
01 01
Function Return bytes
code numbers
05 00 11
Function Switch value
code address
05 00 11
Function Switch value
code address
00 08
Read switch value
CRC parity code
numbers
03
CRC parity
Digital output value
FF 00
Write value CRC parity code
FF 00
CRC parity
Write value
3C 09
11 89
code
DC 3F
DC 3F
code