NCR NCR7454 manual Brightness Adjustment

				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.
Description:	This command is a request for the Retail VFD to return an ASCII string
	with detailed product information.