Hardware Handshaking - Symbol LS 5700 Product Reference Manual

LS 5700/LS 5800 Product Reference Guide
RS-232C Port Auxiliary Options

Hardware Handshaking

The data interface consists of an RS-232C port.
The port has been designed to operate either with or
without the hardware handshaking lines, Request to Send
(RTS), and Clear to Send (CTS).
If Standard RTS/CTS handshaking is selected, scan data is
transmitted according to the following sequence:
•
The controller reads the CTS line for activity. If CTS
is asserted, the controller waits up to 2 seconds for
the host to negate the CTS line. If, after 2 seconds the
CTS line is still asserted, the scanner sounds a
transmit error and any scanned data is lost.
•
When the CTS line is negated, the controller asserts
the RTS line and waits up to 2 seconds for the host to
assert CTS. When the host asserts CTS, data is
transmitted. If, after 2 seconds, the CTS line is not
asserted, the scanner sounds a transmit error and
discards the data.
•
When data transmission is complete, the controller
negates RTS 10 msec after sending the last character.
•
The host should respond by negating CTS. The
controller checks for a negated CTS upon the next
transmission of data.
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