Rs232 Interface - Godex GS200 User Manual

3-3 RS232 interface

Flow control:
None- The communication only uses TXD and RXD signals without any hardware or software
handshaking protocol.
RTS/CTS- If the scanner requests to send the barcode data to host computer, it will issue the RTS
signal first, wait for the CTS signal from the host computer, and then perform the normal data
communication. If there is no replied CTS signal from the host computer after the Response delay
timeout, the scanner will issue an error indication. By setting (Host idle: Low RTS or Host idle: High
RTS), the scanner can be set to match the Serial Host RTS line.
ACK/NAK- If Decode data packet format is set to Packeted, after barcode data transmitted, the
scanner expects either an ACK (acknowledge) or NAK (not acknowledge) 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 NAK are received, the scanner issues an
error indication and discards the data.When the scanner finishes receiving the command from host, it
will send ACK/NAK to host.
Note: If Decode data packet format is set to Raw, the scanner will not wait for ACK/NAK after
transmitting decoded data completely.
Response delay: This delay is the time that the scanner waits for a handshaking acknowledgment (NAK
or ACK) from the host.
Inter-character delay: This delay is the time that the scanner transfers the each character interval.
Host-character delay: This delay is the time that the scanner waits for the host to send the next character
in serial communication.
Decoded data packet format:
Raw- Scanner sends raw decoded data directly.
Packeted- The decoded data is sent in data packet.
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