Honeywell 2020, Руководство пользователя

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RS-232 Handshaking
RS-232 Handshaking allows control of data transmission from the image scan-
ner using software commands from the host device. CTS/RTS operates in
mode 2. When this feature is turned
Off , no data flow control is used. When
Data Flow Control is turned On , the host device suspends transmission by
sending the XOFF character (DC3, hex 13) to the image scanner. To resume
transmission, the host sends the XON character (DC1, hex 11). Data transmis-
sion continues where it left off when XOFF was sent.
Default = Off.
Host ACK Selection
Some applications require that the host terminal (or server) approve or reject
incoming barcode data and notify the operator of these actions. These applica-
tions require that the host maintain control over the response indicators emitted
from the image scanner. Turning on Host ACK configures the image scanner to
respond to commands from the host system.
Note: System performance degrades when using Host ACK at rates lower than
9600 baud.
The following criteria must be met for the Host ACK to work correctly:
• The cordless system must be configured for Host Port RS-232 (terminal ID =
000) or USB COM Emulation (terminal ID = 130).
• RTS/CTS is defaulted off. You must enable it if the host system requires it.
• Host ACK must be set to On ( page 2-20 ).
• The host terminal software must be capable of interpreting the barcode data,
make decisions based on the data content, and send out appropriate escape
commands to the image scanner.
RTS/CTS On
* XON/OFF Off
* RTS/CTS Off
XON/XOFF On
ACK/NAK On
* ACK/NAK Off