PSC SP400rf, Programming Manual

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G
ENERAL
F
EATURES
R44-1027
75
C
OMMUNICATIONS
P
ROTOCOL
The
SP400RF
allows configuration of several different commands that can
be sent and received by the scanner, Base Station and host terminal.
Programming labels to set these options and their descriptions can be
found on the following pages. Configurable commands are:
ACK — Acknowledge. The host message was received and processed
correctly, and no data was requested from the scanner or Base
Station. (0x06)
CTS — Clear to Send. This is a command sent by an RS-232 host.
When CTS is enabled, the scanner must wait for an active CTS
command from the host before transmitting data. Valid only for
RS-232 interfaces.
ETX — End Transmission. Label transmissions can be "framed" by
optional STX (Start Transmission) and ETX characters, which are
selectable by the user. (Factory default is 000—disabled.)
Item On File — The host, upon receiving a label transmission from
the scanner and comparing the information with its database,
found a match. (0x7E)
Item Not On File — After receiving a label transmission from the
scanner, the host cannot find a match for the label in its database.
(0x7F)
NAK — No Acknowledge. The host message wasn't received
correctly (checksum or parity error, overrun, etc.).
STX — Start Transmission. Label transmissions can be "framed" by
optional STX and ETX (End Transmission) characters, which are
selectable by the user. (Factory default is 000—disabled.)
WACK — Wait for Acknowledge. This is a radio feature. When
enabled, it precedes the ACK signal
1
.
1 In some systems, the ACK response is sent so quickly from the interface that it can
override the WACK signal. In this case, the WACK is never perceived by the scanner.