NCR RealPOS 5977, User Manual

Page: 54 / 172

5-42 NCR 5977 2x20 Display Programming
Brightness Adjustment (Default = 2)
Format
1B 17 nn
Range
01 ≤ nn ≤ 05 (Hex)
Description
This command adjusts the brightness of the entire display. Individual characters or
display positions are not adjusted. On power up, the default brightness setting is
5 (100%).
Note: To change the brightness level, refer to Chapter 8, “Service Support Utility” for
instructions.
nn Brightness
01 20%
02 40%
03 60%
04 80%
05 100%
Read Display ID Byte
Format
1B 18
Returns
0x8A
Description
This command is a request for the Retail Display to return a identifier. The Retail
Display returns one byte (0x8A) that identifies the Retail Display as a 2x20 with 7x9 dot
matrix. Since true bi–directional communications are not available for the parallel
interface, a unique interface utilizing the Strobe line as a clock line and the Ack line as a
data line is used.