Motorola SE955 Integration Manual page 234

Serial Interface Specification A - 9
1
TXD
(Host RXD)
6
RXD
(Host TXD)
9
RTS
(Host CTS)
11
5
8
3
CTS
(Host RTS)
10
4
7
2
1. Decoder starts to transmit
2. Host asserts RTS causing transmission pause
3. Decoder grants permission for host to send
4. Host removes request without sending
5. Decoder removes permission
6. Decoder resumes transmission
7. Host requests permission to send ACK
8. Decoder grants permission
9. Host sends ACK
10. Host removes request when finished sending
11. Decoder removes permission
Host Interrupting Decoder's Transmission
Figure A-4