( cell contains both bytes. MSB is spit as-is, LSB is ORed
with r )
( r -- )
: OP2r
CREATE ,
DOES>
@ SPLITB SWAP ( r lsb msb )
A, ( r lsb )
SWAP <<3 ( lsb r<<3 )
OR A,
;
0xed41 OP2r OUT(C)r,
0xed40 OP2r INr(C),