Code:
   LDS r23, {gl_read} 
$end Asm 

If Gl_rstflag = 1 Then 
   !OR r23, r24                                             ' bit setzen 
Else 
   COM r24                                                  ' invertieren 
   !AND r23, r24                                            ' bit löschen 
End If 

   !STS {Gl_pix}, r23