User Manual PLC-3 FAMILY I/0 Instruction Manual

Binary Command Language
Appendix A
A-9
Table A.C
Response
Code
HEX code Response Description
00 Success Operation was completed as requested.
01 Size Too Big Operation stopped because the response was too big to fit in the
response block. Success or failure depends on the operation.
02 Available Interpretation of this response depends on the operation. See the
appropriate command descriptions for details.
03 Unavailable Interpretation of this response depends on the operation. See the
appropriate command descriptions for details.
04 Address Does Not Exist The specified address has not been allocated.
05 Address Invalid This response is returned when the specified start address is valid, but
another address used in the operation has not been allocated.
06 Access Not Allowed The channel does not have access to the area specified for the
purpose requested.
07 Allocated The function or resource requested is allocated and therefore
unavailable (unless it is already allocated to your channel).
08 Address Not Complete The address given is not specified to a low enough level to perform
the requested function.
09 Unknown Command The scanner does not recognize the command code.
0A Invalid Parameter A parameter in the command block is invalid.
0D Processor Error
0E Processor Error
0F No Privilege One or more privileges required for the attempted operation are not
assigned to the channel.
FF Unknown Failure The function failed for a reason which cannot be described by any
other response code.
Initializing Communications
To initiate communications with the scanner the master sends a break
character followed by a CCR. The CCR should have the reset
communications bit (bit 0) of the control code set. This instructs the
scanner to return to its initial communications state, including resetting the
command block sequence and the response block sequence count.
The master must see break go away before sending the CCR. The scanner
sends break for a character timeout period. The scanner identifies a break
character as any high state (voltage) which remains on the line longer than
the time required to transmit one character (byte). The approximate
character times are listed in Table A.D.