月日中断系统双语教学黄英《单片机原理及应用》讲义.docVIP

Chapter 6 Interrupt System and Timer System 主讲教师：黄英 6.1 Interrupt system Contents： 6.1.1 Introduction of Interrupt Technology 1 6.1.2 Interrupt Sources 1 1. External Interrupts 1 2. Timer Interrupts 2 3. Serial Port Interrupt 2 6.1.3 Interrupt Control 2 1. Timer/Counter Control Register（TCON） 2 2. Serial Port Control Register（SCON） 3 3. Interrupt Enable Register（IE） 3 4. Interrupt Priority Register（IP） 4 5. Interrupt Priority Control Rules 4 6. Interrupt Initialization 5 6.1.4 Interrupt Process 5 1. Interrupt Sample 5 2. Interrupt Query 5 3. Interrupt Response 5 4. Interrupt Request Repeal 6 6.1.5 Flow Chart of Interrupt Service 7 6.1.1 Introduction of Interrupt Technology ?A effective method to solve resource competition. ?Lets multitask share one resource: Resource sharing technology. ?Mainly used in real time control. 2 6.1.2 Interrupt Sources ?8051 provides 5 interrupt sources: m Two external interrupts Two timer interrupts One serial port interrupt ?5 interrupt vectors are assigned in a fixed location.e （1） Serial Port interrupt： 0023H～002AH（8 bytes） （2）Timer/Counter 1 interrupt： 001BH～0022H（8 bytes） （3） External Interrupt 1： 0013H～001AH（8 bytes） （4）Timer/Counter 0 interrupt： 000BH～0012H（8 bytes） （5） External Interrupt 0： 0003H～000AH（8 bytes） · The interrupt causes the CPU to jump to the related location, where it has a no-condition jump instruction（LJMP/AJMP/SJMP）pointed to service routine. 1. External Interrupts · External Interrupts: /P3.2, /P3.3 （generated from external device） · Signal Modes: （1）Low Level active （2）Falling edge active 2. Timer Interrupts · Timer0, Timer1 · When counting overflows: A timer interrupt is generated. Timer overflow flag（TF0/TF1）is set by internal hardware circuit. 3. Serial Port Interrupt · When serial port receives/transmits a group of serial data: A serial port interrupt is generated. Receive Flag / Transmit Flag（RI/TI）is set by internal hardware circuit. 6.1.3 Interrup