8259A的功能及其与MCS-51单片机的接口技术

The Functions of 8259A and the Technique of 8259A-MCS-51COC Interface

8 2 5 9A可扩展外部中断源的数目 ,又有多种中断管理方式 .文中阐述 82 5 9A的内部结构、中断操作功能和执行中断过程并介绍与单片机的接口电路和应用程序 .该接口电路解决了锁存器与译码器之间的接口方式问题 ,又克服了 82 5 9A与MCS - 5 1系列芯片的信号的不兼容性 .因此 ,只要在程序中利用相应的指令 ,就可产生 82 5 9A所需的中断应答信号 .

The number of the external interrupt sources can be expanded in 8259A. It also has multiple interrupt management modes. In this paper, the internal structure, the interrupt operation functions and the execution interruption process of 8259A are expounded. It also introduced the 8259A-COC interface circuit and the application program about it.In this interface circuit,the interface methods between lock-exister and decoder is solved.It also overcomes the incompatibility of 8259A with signals of MCS-51 series chip.Therefore in the programe,so long as is used of the corresponding instructions,is caused generation of the necessary interrupt answer signals for 8259A.