Unitech MS588, Руководство пользователя

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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:
z
The digital 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.
z
When the CTS line is de-asserted, the digital 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.
z
When data transmission completes, the digital scanner de-asserts RTS 10 msec
after sending the last character.
z
The host should respond by negating CTS. The digital 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 ms between characters, the digital scanner aborts
transmission, sounds a transmission error, and discards the data.
If this communication sequence fails, the digital 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.
z
None : Scan this bar code to disable hardware handshaking.
z
Standard RTS/CTS : Scan this bar code to select Standard RTS/CTS Hardware
Handshaking.