L4 BSET PC ORG @ 0x12 + ! ( pushRS )
IX INCss,
0 IX+ L LDIXYr,
1 IX+ H LDIXYr,
RET,
PC ORG @ 0x15 + ! ( popRS )
L 0 IX+ LDrIXY,
H 1 IX+ LDrIXY,
IX DECss,