( Core words )
( KEY and EMIT are not defined here. There're
  expected to be defined in platform-specific code. )

CODE EXECUTE
    DE POP,
    chkPS,
    JR, lblexec BWR      ( execute-B301 )

CODE ROT ( a b c -- b c a )
    HL POP, ( C ) DE POP, ( B ) BC POP, ( A )
    chkPS,
    DE PUSH, ( B ) HL PUSH, ( C ) BC PUSH, ( A )
;CODE