NAME   rev ADDR type chip Description
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BLTSIZH  h 05E  W    A    Blitter H size & start (11 bit width)

         BIT# 15 14 13 12 11 10  09 08 07 06 05 04 03 02 01 00
               x  x  x  x  x w10 w9 w8 w7 w6 w5 w4 w3 w2 w1 w0

         See also: BLTSIZV