我用的芯片是LPC2119,其中要用到P0.5口输出方波,我写入以下代码可是P0.5引脚保持低电位,不知道代码那里错了?<br /><br /> INCLUDE LPC2294.INC<br />;-------------------------------------------- <br /> AREA TEST,CODE,READONLY<br /> ENTRY <br />;-------------------------------------------- <br />MAIN <br />;------------引脚连接MAT0.1------------------<br /> ldr r0,=PINSEL0<br /> mov r1,#0x800<br /> str r1,[r0] ;p0.5-->mat0.1<br />;------------定时器0初试化-------------------<br /> ldr r0,=T0MR1<br /> ldr r1,=0x00000bb7<br /> str r1,[r0] ;溢出时间MR1<br /> ldr r0,=T0MCR<br /> mov r1,#0x10 <br /> str r1,[r0] ;MR1复位<br /> ldr r0,=T0EMR <br /> mov r1,#0xc0<br /> str r1,[r0] ;MAT0.1(p0.5)外部匹配引脚翻转<br /> ldr r0,=T0TCR <br /> mov r1,#0x03<br /> str r1,[r0] <br /> ldr r0,=T0TCR<br /> mov r1,#0x01<br /> str r1,[r0] ;起动定时器<br />;----------------------------------------------<br /> B .<br />;---------------------------------------------- <br /> END |
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