Motorola SYMBOL DS6707, Product Reference Manual

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RS-232 Interface 8 - 13
Check Receive Errors
Select whether or not to check the parity, framing, and overrun of received characters. The parity value of received
characters is verified against the parity parameter selected above.
Hardware Handshaking
The data interface consists of an RS-232 port designed to operate either with or without the hardware handshaking
lines, Request to Send (RTS), and Clear to Send (CTS).
Disable Standard RTS/CTS handshaking to transmit scan data as it becomes available. Select Standard RTS/CTS
handshaking to transmit scan data according to the following sequence:
•
The digital imager scanner reads the CTS line for activity. If CTS is asserted, the digital imager scanner waits
up to Host Serial Response Time-out for the host to de-assert the CTS line. If, after Host Serial Response
Time-out (default), the CTS line is still asserted, the digital imager scanner sounds a transmit error, and
discards any scanned data.
•
When the CTS line is de-asserted, the digital imager scanner asserts the RTS line and waits up to Host Serial
Response Time-out for the host to assert CTS. When the host asserts CTS, the scanner transmits data. If,
after Host Serial Response Time-out (default), the CTS line is not asserted, the digital imager scanner
sounds a transmit error, and discards the data.
•
When data transmission completes, the digital imager scanner de-asserts RTS 10 msec after sending the
last character.
•
The host should respond by negating CTS. The digital imager scanner checks for a de-asserted CTS upon
the next transmission of data.
During data transmission, the CTS line should be asserted. If CTS is deasserted for more than 50 ms between
characters, the scanner aborts transmission, sounds a transmission error, and discards the data.
If this communication sequence fails, the digital imager scanner issues an error indication. In this case, the data is
lost and must be rescanned.
If hardware handshaking and software handshaking are both enabled, hardware handshaking takes precedence.
*
Check For Received Errors
Do Not Check For Received Errors
NOTE The DTR signal is jumpered to the active state.