Control IO port operation by buttons-EEWORLD

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Today, we have a certain understanding of the microcontroller keys. Microcontrollers are divided into stand-alone keyboards and matrix keyboards. The stand-alone type occupies more IO port resources and is suitable for control operations with fewer keys. Its advantage is that the design and programming are clear at a glance and relatively simple. The matrix type occupies fewer IO ports and is suitable for operations that have high requirements for keys and where IO port resources are relatively precious. The two have their own advantages and disadvantages. In future applications, they must be designed according to needs, especially the matrix type must use the high and low level detection of row and column lines and the principle of processing data information must be remembered.

Below I will write a simple program that I learned today to control the operation of the IO port LED light through buttons. Haha, it can deepen my understanding of button operation (ELSE statement).

#include

#define uint unsigned int

#define uchar unsigned char

sbit DIPswitch1=P3^0;

sbit DIPswitch2=P3^1;

sbit redLED1=P1^0;

sbit blueLED1=P1^1;

sbit greenLED1=P1^2;

sbit yellowLED1=P1^3;

sbit redLED2=P1^4;

sbit blueLED2=P1^5;

sbit greenLED2=P1^6;

sbit yellowLED2=P1^7;

void delay(void)

{ uint i;

for(i=0;i<35530;i++);

}

void main(void)

{

P1=0XFF;

P3=0XFF; //Set

while(1)

{

if(DIPswitch1==0)

{

redLED1=~redLED1;

yellowLED2=~yellowLED2; //Judge whether button 1 is at a low level. If so, implement bitwise inversion of pins 1 and 7 of port P0

delay();}//delay operation

else if(DIPswitch2==0)

{

P1=~P1; //When button 2 is low, all bits of port P0 are inverted and flash

}

else

{

P1=0X00; //If both buttons 1 and VS2 are high, all lights will be on

}

The working principle is that when button 1 is at a low level, pins 1 and 7 of P1 port are bitwise inverted to realize the flashing of LED lights. When button 2 is at a low level, all lights of P1 port realize the bitwise inversion function and all lights flash. When buttons 1 and 2 are both at a high level, P1 port is at a low level and all lights are on.

This hardware circuit is that P3^0 and P3^1 control buttons 1 and 2; P1 port controls eight LED lights.

Haha, I am still learning the dynamic and static control of digital tubes. Now I should be able to master the basic static control, and I will try to finish learning the dynamic control in the next two days. Come on.

Due to time constraints, I will not write about the working system of the microcontroller here.

Reference address：Control IO port operation by buttons

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