Intelligent Vehicle Learning (vii)--implementation of key matrix

First, the principle of explanation

is the key matrix code to write a description, that is, K5 to K7 first output high, and K1 and K4 are tuned into the pull-up input, if detected K1 to K4 has a change to 0, indicating that there is a key press down, immediately convert, yes K1 to K4 set to output high level, and then read K5 to K7 for the pull-up input, Then read to the point of 0, the two data will be able to determine that the button was pressed.

Second, based on KVL25 code writing:

1. header file

#ifndef __keysquare_h#define__keysquare_h/*********** macro Definition ************/#defineKeysquare_k1 PTD7#defineKeysquare_k2 PTD6#defineKeysquare_k3 PTD5#defineKeysquare_k4 PTD4#defineKeysquare_k5 PTD3#defineKeysquare_k6 PTD2#defineKeysquare_k7 PTD1#defineKEYNUM1 1#defineKeynum2 2#defineKEYNUM3 3#defineKEYNUM4 4#defineKEYNUM5 5#defineKEYNUM6 6#defineKEYNUM7 7#defineKEYNUM8 8#defineKEYNUM9 9#defineKEYNUM10 10#defineKEYNUM11 11#defineKEYNUM12 12/*****************************//*********** function Nerve ***********/intKeyboard_get (void);/*****************************/#endif

2. Source Files

#include"include.h"#include"Common.h"#include"OLED.h"#include"gpio.h"#include"KeySquare.h"#include"Lptmr.h"intKeyboard_get (void) {unsignedCharTempdata=0x00; unsignedCharBdata=0x00; intkeynum=0; //set as input to detectGpio_init (KEYSQUARE_K1, GPI,1); Gpio_init (Keysquare_k2, GPI,1); Gpio_init (Keysquare_k3, GPI,1); Gpio_init (Keysquare_k4, GPI,1); //set to pull-upPort_init_noalt (Keysquare_k1,pullup);   Port_init_noalt (Keysquare_k2,pullup);   Port_init_noalt (Keysquare_k3,pullup);      Port_init_noalt (Keysquare_k4,pullup); //set to OutputGpio_init (Keysquare_k5,gpo,0); Gpio_init (Keysquare_k6,gpo,0); Gpio_init (Keysquare_k7,gpo,0); Lptmr_delay_us (4); TempData=Gpio_get (KEYSQUARE_K1); TempData+ = Gpio_get (KEYSQUARE_K2) <<1; TempData+ = Gpio_get (KEYSQUARE_K3) <<2; TempData+ = Gpio_get (KEYSQUARE_K4) <<3; if(TempData! =0xFF) {bdata= (TempData <<4) |0x00; Gpio_init (Keysquare_k1, GPO,0); Gpio_init (Keysquare_k2, GPO,0); Gpio_init (Keysquare_k3, GPO,0); Gpio_init (Keysquare_k4, GPO,0); Gpio_init (KEYSQUARE_K5,GPI,1); Gpio_init (KEYSQUARE_K6,GPI,1); Gpio_init (KEYSQUARE_K7,GPI,1); //Pull UpPort_init_noalt (Keysquare_k5,pullup);       Port_init_noalt (Keysquare_k6,pullup);       Port_init_noalt (Keysquare_k7,pullup); Lptmr_delay_us (4); TempData=Gpio_get (KEYSQUARE_K5); TempData+ = Gpio_get (keysquare_k6) <<1; TempData+ = Gpio_get (keysquare_k7) <<2; Bdata+=TempData; Switch(bdata) { Case  the: KEYNUM=KEYNUM1; Break;  Case 214: keynum=keynum2; Break;  Case 182: keynum=keynum3; Break;  Case 118: KEYNUM=KEYNUM4; Break;  Case 229: KEYNUM=KEYNUM5; Break;  Case 213: KEYNUM=KEYNUM6; Break;  Case 181: KEYNUM=KEYNUM7; Break;  Case 117: KEYNUM=KEYNUM8; Break;  Case 227: KEYNUM=KEYNUM9; Break;  Case 211: KEYNUM=KEYNUM10; Break;  Case 179: KEYNUM=KEYNUM11; Break;  Case  the: KEYNUM=KEYNUM12; Break; default: Break; }    }    returnKeynum;}

Third, the use of instructions

When used, a call is made in the main function, and each time a value is returned, 0 means that it is not pressed, or the corresponding key value is returned.

Intelligent Vehicle Learning (vii)--implementation of key matrix