COMMUNICATIONS PROTOCOL
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
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
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
WACK — Wait for Acknowledge. This is a radio feature. When enabled, it precedes the ACK signal1.
GENERAL FEATURES
1In 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.
75 |
