Agnus/ Read/ Denise/ Register Address Write Paula Function -------- ------- ----- ------- -------- BLTxPTH 050 W A( E ) Blitter pointer to x (high 3 bits, 5 bits if ECS) BLTxPTL 052 W A Blitter pointer to x (low 15 bits) This pair of registers contains the 18-bit address of blitter source (x=A,B,C) or destination (x=D) DMA data. This pointer must be preloaded with the starting address of the data to be processed by the blitter. After the blitter is finished, it will contain the last data address (plus increment and modulo). LINE DRAW BLTAPTL is used as an accumulator LINE DRAW register and must be preloaded with LINE DRAW the starting value of (2Y-X) where LINE DRAW Y/X is the line slope. BLTCPT and LINE DRAW BLTDPT (both H and L) must be LINE DRAW preloaded with the starting address LINE DRAW of the line.
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