User Manual

108 • Appendix
Mailbox Command References
WAGO-I/O-SYSTEM 750
I/O Modules
Response
Byte 2
7
2
6
2
5
2
4
2
3
2
2
2
1
2
0
0 MBX_DLD_CONT
1 T MBX_RESULT
2 DATA
3 DATA
4 DATA
5 DATA
6 OPTIONAL DATA
... ...
33 OPTIONAL DATA
Return values
Parameter Value Description
MBX_CMD_OK No error occurred. The block transfer
has been continued.
MBX_CMD_DENIED_NOT_
APPLICABLE
There is no active transfer.
The command is invalid.
MBX_RESULT
MBX_CMD_OUT_OF_RANGE An attempt was made to transfer more
than 512 bytes.
DATA
OPTIONAL
DATA
[0x00...0xFF] Transmitted data bytes
In configuration mode, the number of
data bytes is based on the mailbox
size - 2. During data upload to the
module, data bytes are initialized in
the response with 0x00 and can be
ignored.