Symbol Technologies LS 9208 Barcode Reader User Manual


 
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LS 9208 Product Reference Guide
ACK/NAK
When this option is selected, after transmitting data, the scanner expects either an ACK or
NAK response from the host. When a NAK is received, the scanner transmits the same data
again and waits for either an ACK or NAK. After three unsuccessful attempts to send data
when NAKs are received, the scanner issues an error indication and discards the data.
The scanner waits up to the programmable Host Serial Response Time-out to receive an
ACK or NAK. If the scanner does not get a response in this time, it issues an error indication
and discards the data. There are no retries when a time-out occurs.
ACK/NAK
ENQ
When this option is selected, the scanner waits for an ENQ character from the host before
transmitting data. If an ENQ is not received within the Host Serial Response Time-out, the
scanner issues an error indication and discards the data. The host must transmit an ENQ
character at least every Host Serial Response Time-out to prevent transmission errors.
ENQ