Star MCM300 SERIES, Manual Manual

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PROTOCOL 6
6-1 Communication Procedure
Basic procedure of communication is as follows.
Connected device MCP/MCM 300
Send Command
→
Receive Command
Receive ACK
←
Send ACK
Command processing
Receive response
←
Send response
Send ACK
→
Receive ACK
6-2 Command / Response transfer format
Command transfer format
BCC is exclusive OR between command and ETX.
STX Command Data ETX BCC
Response transfer format
STX Command Status Data ETX BCC
6-3 Transmission Control Characters
Character Code Function
STX 02h Start of Text
ETX 03h End of Text
ACK 06h Acknowledge
NAK 15h Negative Acknowledge
DLE 10h Data Link Escape
LF 0Ah Line Feed (for Human Readable Area Print)
BCC - Block Check Character