Panasonic FP2 ET-LAN Technical Manual page 254

Command code and Response code
Table of command
Command code
50H
51H
52H
53H
Note:
The corresponding response code is a value that is the reverse of the first bit (0 → 1) of the
command code (1-byte binary code).
The end code for a normal response is FFH, while that when an error occurs is an error
code. (See "MEWTOCOL Error Codes" on Chapter 14.3.)
14-26
Description
Writing to a data area
Reading from a data area
Writing of contact information
Reading of contact information
Corresponding response code
D0H
D1H
D2H
D3H