Sandbox collapse test

$FFFF8A38.W|RW|BLT_LPB|Lines per BOB                         (0:65536)|BLT

$FFFF8A3A.B|RW|BLT_HTO|Halftone Operation %______xx |BLT

$FFFF8A3A  BLT_HOP  Halftone Operation      bits 1-0 used

 0   all ones ($FFFF)
 1   halftone RAM word
 2   source word
 3   source word AND halftone RAM word

$FFFF8A3B.B|RW|BLT_LGO|Logical Operation                    %____xxxx |BLT
$FFFF8A3C.B|RW|BLT_LNM|Line Number                          %BHS_xxxx |BLT