请教一个ClearPending的问题#define    ClearPending(bit) {\
            rSRCPND = bit;\
            rINTPND = bit;\
            rINTPND;\
        }    
2440的英文手册中When the interrupt
sources request interrupt the service, the corresponding bits of SRCPND register are set to 1, and at the same time,，意思是可以同时多位为1，而INTPND一个时刻只能一个为1，那这样直接等于来清零的话，对其他位没影响吗？清零的话到底是置1还是置0呢？

so the service routine must clear the
pending condition by writing a 1 to the corresponding bit in the SRCPND register first and then clear the pending
condition in the INTPND registers by using the same method.
好像解决了，手册上貌似说清零也是写1？