(3) Frame example
Example that requests reading bit of 20~28 to station number 1 server acting as modbus RTU mode
(a) Request frame
Classification Station no.
Function
code
Address Data size
Error check
Upper byte Lower byte Upper byte Lower byte
Frame 01 01 00 13 00 13 CRC
(b) Response frame (In case receiving normal frame)
Classification Station no.
No. of byte Data Error check
Frame 01 01 03 12 31 05 CRC
(c) Response frame (In case of receiving abnormal frame)
Classification Station no. Function code Exceptional code Error check
Frame 01 81 02 CRC