Rockwell Automation 2755 2D Hand-Held Scanner - Manual (Page 66)

Communication Setup (Synapse Cable) 5–5
Publication 2755-6.4
Hardware Handshaking
When enabled, handshaking verifies the readiness of a receiving
device before data is transmitted. You can enable or disable the
hardware handshaking lines. The DTR (Data Terminal Ready)
signal is either active high or low (see below).
This is how the scanner handshaking functions:
1. The scanner checks the Clear to Send (CTS) line. If CTS is
active, the scanner will wait for up to 2 seconds and check the
line again. If the line is still active, the scanner will provide an
audible beep and any scanned data will be lost.
2. If the CTS line is not active, the scanner will assert the Request to
Send (RTS) line and wait for two seconds for the host to assert
the CTS line. When the host asserts the CTS line, the scanner
transmits the data.
3. After the transmission is completed, the scanner negates the RTS.
4. The host device should then negate CTS. The scanner checks the
CTS line on the next transmission.
RTS State
Selects the active state for the Request to Send (RTS) signal.
Make sure that this setting matches the requirements of the host
device. The selections are:
•
RTS State Low (default)
•
RTS State High