Function Code 03H: Read Holding Register; Function Code 06H: Write A Single Holding Register - Ebyte E90-DTU User Manual

Chengdu Ebyte Electronic Technology Co., Ltd.
CRC check code

6.1.10 Function code 03H: read holding register

For example: the host wants to read the data of 2 holding registers whose slave address is 01H and the starting
register address is 05H, host sends：
start register
Number of
CRC check
If the data of slave holding registers 05H and 06H are 1122H and 3344H, slave returns：
Register 05H data
Register 06H data
CRC check code

6.1.11 Function code 06H: write a single holding register

For example: the host writes the data of 9988H to the register with the slave address of 01H and the register
address of 0050H, Host sends:
register address
write value
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low byte
high byte
Host sends
address code
function code
high byte
address low byte
high byte
registers low byte
low byte
high byte
Slave return
address code
function code
number of bytes
high byte
low byte
high byte
low byte
low byte
high byte
Host sends
address code
function code
high byte
low byte
high byte
low byte
E90-DTU(400SL30L)_UserManual_EN
AD
F3
Send data (HEX)
01
03
00
05
00
02
D4
0A
Send data (HEX)
01
03
04
11
22
33
44
4B
C6
Send data (HEX)
01
06
00
50
99
88
30