Datalogic DSM0400, Руководство по продукции

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References
214 DSM0400 Fixed Mount Area Imager Bar Code Reader
RS-232 Parameters
RS-232 Only
Baud Rate
Baud rate is the number of bits of data transmitted per second. Set the scan-
ner's baud rate to match the baud rate setting of the host device. With an
improper baud rate setting, data may not reach the host correctly.
Data Bits
This parameter allows the reader to interface with devices requiring a 7-bit or
8-bit ASCII protocol for sending and receiving data.
Stop Bits
The stop bit(s) at the end of each transmitted character marks the end of trans-
mission of one character and prepares the receiving device for the next charac-
ter in the serial data stream. The number of stop bits selected (one or two)
depends on the number the receiving terminal is programmed to accommo-
date. Set the number of stop bits to match host device requirements.
Parity
This feature specifies parity required for sending and receiving data. A parity
check bit is the most significant bit of each ASCII coded character. Select the
parity type according to host device requirements.
• Select None when no parity bit is required.
• Select Odd parity and the parity bit value is set to 0 or 1, based on data, to
ensure that an odd number of 1 bits are contained in the coded character.
• Select Even parity ASCII Chart on page 239 the parity bit value is set to 0 or 1,
based on data, to ensure that an even number of 1 bits are contained in
the coded character.
Handshaking Control
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). Handshaking Control includes the following options:
• - None - no hardware handshaking lines, only TX and RX communication
lines are used.
• RTS — RTS is asserted during transmissions. CTS is ignored.
• RTS/CTS — RTS is asserted during transmissions. CTS gates transmis-
sions.
• RTS On/CTS — RTS is always asserted. CTS gates transmissions.