NCR 7454 - Brightness Adjustment; Read Display ID Byte; Read Display ID String

Chapter 6: NCR 7454 4x20 Customer Display 6-15
Brightness Adjustment
Format: 1B 17 nn
Range: 01 ≤ nn ≤ 05
Description: Adjusts the brightness of the entire display. Individual characters or display
positions will not be adjusted. On power up, the default brightness setting is 5
(100%).
Nn
Brightness
01 0%
02 25%
03 50%
04 75%
05 100%
Read Display ID Byte
Format: 1B 18
Returns: 0x8E
Description: This command is a request for the Retail VFD to return a identifier. The
Retail VFD returns one byte (0x8E) that identifies the Retail VFD as a
4x20 with 5x7 dot matrix.
Read Display ID String
Format: 1B 19
Returns: 0x1D, "NCR_008-0221552,_F/W_V1.00.01"
Where 0x1D is a 1 byte string length indicator which indicates the
length of the string that follows the string length indicator. For
example, 1DH characters are sent after the string length indicator.
Note: “_”indicates a space character (20H). The quotation marks “” are
not part of the string and are not returned.