NCR RealPOS 70, User Manual

Page: 237 / 306

Chapter 11: APA Customer Display Interface 11-11
Invert Screen (0Ah)
This command logically inverts (0 ʹ s become 1 ʹ s, 1 ʹ s become 0 ʹ s) the
contents of DDRAM selected by the H and G bits. In the monochrome
mode (G=0) only Page 0 is affected. The XAR, the YAR, and the data
control bits are not affected by this command.
Reserved (0Bh - 0Fh)
These codes are reserved for future use and are currently ignored by
the module.
Character Codes (10h - FFh)
Data values received by the module that are within the range 10h
through FFh, are character codes. The character selected from the
character table by the character code is written, using the current
character write and data write modes, into the DDRAM location
addressed by the XAR, the YAR, the data control bits. The XAR and
YAR point to the DDRAM location that the left hand side of a 5x7
(upper left hand side of a 10x14) character will be stored.
This command adds 1 *blank column to 5x7 characters or 2 *blank
columns to 10x14 characters, for character spacing.
This command also automatically increments (I/D=0) or decrements
(I/D=1) the X and Y address registers to point to the next character
(some characters are wider than others, see font table for sizes). YAR
overflows, 127 to 0, increment the XAR (by 2 for 10x14 characters) and
YAR underflows, 0 to 127, decrement the XAR (by 2 for 10x14
characters). Characters are top ‐ justified leaving the bottom pixel row (2
pixel rows for 10x14 characters) *blank.
* ʺ blank ʺ is dependent on the current data write mode.