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RS-232 Parameter Defaults
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 scanner reads the CTS line for activity. If CTS is asserted, the 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 scanner sounds a
transmit error, and discards any scanned data.
• When the CTS line is de-asserted, the 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 scanner sounds a transmit error, and discards the data.
• When data transmission completes, the scanner de-asserts RTS 10 msec after sending
the last character.
• The host should respond by negating CTS. The scanner 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 deasserted for
more than 50 msec between characters, the scanner aborts transmission, sounds a
transmission error, and discards the data.
If this communication sequence fails, the 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.
Note: The DTR signal is jumpered to the active state.
• None: Scan this programming symbol to disable hardware handshaking.
• Standard RTS/CTS: Scan this programming symbol to select Standard RTS/CTS
Hardware Handshaking.
• RTS/CTS Option 1: If you select RTS/CTS Option 1, the scanner asserts RTS before
transmitting and ignores the state of CTS. The scanner de-asserts RTS when the
transmission completes.
• RTS/CTS Option 2: If you select Option 2, RTS is always high or low (user-programmed
logic level). However, the scanner waits for CTS to be asserted before transmitting data.
If CTS is not asserted within Host Serial Response Time-out (default), the scanner
issues an error indication and discards the data.
• RTS/CTS Option 3: If you select Option 3, the scanner asserts RTS prior to any data
transmission, regardless of the state of CTS. The scanner waits up to Host Serial
Response Time-out (default) for CTS to be asserted. If CTS is not asserted during this
time, the scanner issues an error indication and discards the data. The scanner de-asserts
RTS when transmission is complete.
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HS-360X Handheld DPM Scanner User Manual
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