( a -- k12, absolute addr a, relative to PC in a k12 addr )
: _r7ffc DUP 0x7ff > IF _oor THEN ;
: _raddr12
    PC - DUP 0< IF 0x800 + _r7ffc 0x800 OR ELSE _r7ffc THEN ;
0xc0 CONSTANT RJMPOP
0xd0 CONSTANT RCALLOP
: RJMP, _raddr12 RJMPOP 8 LSHIFT OR A,, ;
: RCALL, _raddr12 RCALLOP 8 LSHIFT OR A,, ;