Lexmark C910 - Page 94

PCL
2-82
Delta Row
Delta Row is a compression mode that identifies and transmits only those bytes
different from the ones in a preceding row. The control byte consists of two parts:
• High 3 bits: Number of bytes to replace +1 (1 to 8).
• Low 5 bits: Offset from last unmodified byte (0-30); if the offset is 31, the next
byte(s) is added to the offset until the next byte is not 255.
Example:
ESC
*p300x1200Y |Move cursor to 1" x 4"
ESC
*b3M |Set compression to Delta Row
ESC
*r1A |Start raster graphics at current position
|Num Offset
ESC
*b9W 'E0FFFFFFFFFFFFFFFF'x |'111 00000'b=8 at 0: 'FFFFFFFFFFFFFFFF'x
ESC
*b9W 'E08000000000000001'x |8 at 0: '8000000000000001'x
ESC
*b0W |No bytes change
...
ESC
*b0W |No bytes change
ESC
*b9W 'E0FFFFFFFFFFFFFFFF'x |8 at 0: '8FFFFFFFFFFFFFF'x
ESC
*rB |End graphics