xf_test.asm

控制XF引脚周期性变化

           .mmregs
	       .def CodeStart,_c_int00
_c_int00	      
	       .text

CodeStart:
                                                                                                                                                              SSBX XF           ;XF置1
	        CALL Delay
	        RSBX XF
	        CALL Delay 
	        B CodeStart

Delay:
            STM #199,AR1
LOOP1:      STM #999,AR2
LOOP2:      BANZ LOOP2,*AR2-
            BANZ LOOP1,*AR1-
	        RET
	        .end