Response Frames - Omron E5AR-T User Manual

■ Response Frames

● Normal Response Frames
● Error Response Frames
(5) Steps 3 and 4 are repeated until the contents of the register have been
shifted 8 bits to the right.
(6) If the end of the message has not been reached, an XOR is taken of the
next byte of the CRC register and the message, the result is returned to
the CRC register, and the procedure is repeated from step (3).
(7) The result (the value in the CRC register) is placed in the lower byte of the
message.
Example of Appending the Result
If the calculated CRC value is H'1234, this is appended as follows to the
command frame:
Function
Slave
code
address Data
Bytes:
1 1
CRC-16 calculation range
Slave Function
address code Data
Bytes:
1 1
CRC-16 calculation range
Slave Function Error
CRC-16
address code code
Bytes:
1 1 1 2
CRC-16 calculation range
The unit number that was specified in the command
Slave address frame is returned here. This is the unit number of the
responding E5AR-T/ER-T.
The function code that was received is returned here.
In an error response frame, "H'80" is added to the value
Function code to indicate that this is an error response.
Example: Received function code = H'03
Error code An end code that indicates the error.
Cyclical Redundancy Check
These two bytes are a check code calculated from the
CRC-16
slave address through the end of the data in hexadeci-
mal.
CRC-16
Low High
H'34 H'12
2
CRC-16
2
Function code in error response frame = H'83
7.2 Frames
7-5