Symbol SE 923, Integration Manual

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SE-923 Scan Engine Integration Guide
Host Requirements
A CMD_ACK or response data must be sent by the decoder within the programmable Serial
Response Time-out to acknowledge receipt of all messages, unless noted otherwise in the
message description section. If the host sends data and does not receive a response within the
programmable serial response time-out, it should resend the message (with the retransmit
status bit set) before declaring a failure. The host should limit the number of retries.
Decoder Requirements
A CMD_ACK or response data must be sent by the decoder within the programmable Serial
Response Time-out to acknowledge receipt of all messages, unless noted otherwise in the
message description section. If the decoder does not receive an ACK within this time period,
it sends the previous message again (retry). The decoder retries twice more (with the
retransmit status bit set) before declaring a transmit error.