NAME   rev ADDR type chip Description
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BLTxMOD    064  W    A    Blitter Modulo x

         This register contains the Modulo for Blitter source (x=A,B,C)
         or Dest (X=D). A Modulo is a number that is automatically
         added to the address at the end of each line, in order that
         the address then points to the start of the next line. Each
         source or destination has it's own Modulo, allowing each
         to be a different size, while an identical area of each is
         used in the Blitter operation.