RS-232 Interface 8 - 11

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 availa ble. Select Standard RTS/CTS
handshaking to transmit scan data according to the following sequence:
•
The device reads the CTS line for activity. If CTS is asserted, the device 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 device sounds a transmit error, and discards any scanned data.
•
When the CTS line is de-asserted, the device asserts the RTS line and waits up to Host S erial Response
Time-out for the host to assert CTS. When the host asserts CTS, the device transmits data. If, after Host
Serial Response Time-out (default), the CTS line is not asserted, the device sounds a transmit error, and
discards the data.
•
When data transmission completes, the device de-asserts RTS 10 msec after sending th e last character.
•
The host should respond by negating CTS. The device checks for a de -asserted CTS upon the next
transmission of data.
During the transmission of data, the CTS line should be asserted. If CTS is deasser ted for more than 50 ms
between characters, the device aborts transmission, sounds a transmis sion error, and discards the data.
If this communication sequence fails, the device issues an error indic ation. In this case, the data is lost and must be
rescanned.
If hardware handshaking and software handshaking are both enabled, hardware hands haking takes precedence.
*Check For Received Errors
Do Not Check For Received Errors
NOTE The DTR signal is jumpered to the active state.