Symbol SE955 Integration Manual page 223

Serial Interface Specification A-7
TXD
(Host RXD)
6
RXD
(Host TXD)
3
RTS
(Host CTS)
5
2
CTS
(Host RTS)
4
1
1. Host requests to send
2. Decoder grants permission
3. BEEP command sent
4. Host removes request
5. Decoder removes permission
6. Decoder ACKs
Figure A-3. Basic Host Initiated Transaction