
REFERENCES
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One way mode:
Host sends a message to STAR Modem™ which passes it to the destination device
via radio. In case of good transmission, the destination device transmits a radio
acknowledgement back to the modem. If received before the Radio Protocol Timeout
expires, STAR Modem™ sends an ACK character to the Host. If the timeout expires
before receiving any acknowledgement, the modem transmits a NACK character.
1 Way Transmission Mode
Two way mode:
Host sends a message to STAR Modem™ which passes it to the destination device
via radio. The destination device transmits the message to the Remote Host which
responds with DATA. This answer is sent to STAR Modem™ through the
destination device. Then, the modem transmits it to the Host.
If the Radio Protocol Timeout expires before the answer from Remote Host is
received by STAR Modem™ or in case the Remote Host does not respond,
STAR Modem™ sends a NACK character to the Host.
2 Way Transmission Mode
NOTE
If the Host continues to send new messages before receiving any
answer from the Remote Host, it is strongly suggested to enable the
handshaking on the Host connected to STAR Modem™ for a
correct functioning.
Message
Message
Remote
Host answer
Remote Host answer
Message
DATA
Host
Remote Host
Message
Message
radio
acknowledgement
ACK/NACK
Host
Remote Host