NCR XR3 (7613), Руководство пользователя

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Chapter 9:
2x20 Customer Display Interface
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:
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.
Character Scrolling Rate
The recommended scrolling rate is at minimum of approximately 350 ms (milliseconds)
interval for this LCD display. Residual images may appear if scrolled at a faster interval
(lesser than 350 ms).