Chapter 4: Programming Set Up
Firmware and software function descriptions for the NCR 5972 Retail Display are presented in this chapter.
Host/Retail Display Command Interface
The Retail Display accepts two types of data: display data and command data. If a byte received from the host is any character except the ESC (0x1B) character, it is processed as a character and displayed on the Retail Display. If an ESC character (0x1B) is received, the subsequent byte(s) is processed as a command. If the subsequent byte is an invalid command it is ignored. If an ESC is received, but no command byte is received immediately, the firmware waits forever if need be and uses the next received byte(s) to complete the command.
Note: Each command consists of at least two bytes. The first byte (0x1B) is a command identifier indicating the next byte(s) is a command byte. The command byte may be followed by parameter or data bytes depending on the command. Also note that the ESC character can be displayed by using the Display ESC Character command.