Symbol LS3408 Product Reference Guide - Miles Data Technologies

RS-232 Interface 6 - 13Software HandshakingThis parameter offers control of the data transmission process in addition to, or instead of, that offered by hardwarehandshaking. There are five options.If software handshaking and hardware handshaking are both enabled, hardware handshaking takes precedence.NoneSelect this option to transmit data immediately. No response is expected from host.ACK/NAK*NoneIf you select this option, after transmitting data, the scanner expects either an ACK or NAK response from the host.When it receives a NAK, the scanner transmits the same data again and waits for either an ACK or NAK. Afterthree unsuccessful attempts to send data after receiving NAKs, the scanner issues an error indication and discardsthe data.The scanner waits up to the programmable Host Serial Response Time-out to receive an ACK or NAK. If thescanner does not get a response in this time, it issues an error indication and discards the data. There are noretries when a time-out occurs.ENQACK/NAKIf you select this option, the scanner waits for an ENQ character from the host before transmitting data. If thescanner does not receive an ENQ within the Host Serial Response Time-out, the scanner issues an error indicationand discards the data. The host must transmit an ENQ character at least every Host Serial Response Time-out toprevent transmission errors.ENQ