模块图片,4位共阳极数码管.
我们使用树莓派wiringPi的库来通过74HC595驱动4位数码管:
C 代码如下:
1 #include <wiringPi.h>
2 #include <stdio.h>
3 #include <stdlib.h>
4 #include <stdint.h>
5 #include <time.h>
6 #define SCLK 12
7 #define RCLK 13
8 #define DIO 14
9 unsigned int code_char[]={0xc0,0xf9,0xa4,0xb0,0x99,0x92,0x82,0xf8,0x80,0x90};
10 unsigned char code_segbit[]={0x01,0x02,0x04,0x08};
11 int pins[3]={SCLK,RCLK,DIO};
12 int init(){
13 int i=0;
14 for(i=0;i<3;i++){
15 pinMode(pins[i],OUTPUT);
16 digitalWrite(pins[i],LOW);
17 }
18 }
19
20 int destroy(){
21 int i=0;
22 for(i=0;i<3;i++){
23 digitalWrite(pins[i],LOW);
24 pinMode(pins[i],INPUT);
25 }
26 }
27
28 void loop(){
29 time_t rawtime;
30 time(&rawtime);
31 struct tm *timeinfo;
32 timeinfo=localtime(&rawtime);
33 digitalWrite(RCLK,LOW);
34 if(timeinfo->tm_min>=10)shiftOut(DIO,SCLK,1,code_char[timeinfo->tm_min%10]);//character
35 else shiftOut(DIO,SCLK,1,code_char[timeinfo->tm_min]);
36 shiftOut(DIO,SCLK,1,code_segbit[0]);//bit
37 digitalWrite(RCLK,HIGH);
38 digitalWrite(RCLK,LOW);
39 if(timeinfo->tm_min>=10)shiftOut(DIO,SCLK,1,code_char[timeinfo->tm_min/10]);//character
40 else shiftOut(DIO,SCLK,1,code_char[0]);
41 shiftOut(DIO,SCLK,1,code_segbit[1]);//bit
42 digitalWrite(RCLK,HIGH);
43 digitalWrite(RCLK,LOW);
44 if(timeinfo->tm_hour>=10)shiftOut(DIO,SCLK,1,code_char[timeinfo->tm_hour%10]);//character
45 else shiftOut(DIO,SCLK,1,code_char[timeinfo->tm_hour]);
46 shiftOut(DIO,SCLK,1,code_segbit[2]);//bit
47 digitalWrite(RCLK,HIGH);
48 digitalWrite(RCLK,LOW);
49 if(timeinfo->tm_hour>=10)shiftOut(DIO,SCLK,1,code_char[timeinfo->tm_hour/10]);//character
50 else shiftOut(DIO,SCLK,1,code_char[0]);
51 shiftOut(DIO,SCLK,1,code_segbit[3]);//bit
52 digitalWrite(RCLK,HIGH);
53 //printf("%d %d\t%d %d %d %d\n",
54 // timeinfo->tm_hour,timeinfo->tm_min,
55 // timeinfo->tm_hour/10,timeinfo->tm_hour%10,
56 // timeinfo->tm_min/10,timeinfo->tm_min%10);
57 delayMicroseconds(10);
58 }
59
60 int main(void){
61 if(wiringPiSetup()==-1) //wiringPiSetupGpio==BCM
62 exit(1);
63 init();
64 while(1) {
65 loop();
66 }
67 destroy();
68 return 0;
69 }
74HC595.h
1 /*
2 * wiringShift.h:
3 * Emulate some of the Arduino wiring functionality.
4 *
5 * Copyright (c) 2009-2012 Gordon Henderson.
6 ***********************************************************************
7 * This file is part of wiringPi:
8 * https://projects.drogon.net/raspberry-pi/wiringpi/
9 *
10 * wiringPi is free software: you can redistribute it and/or modify
11 * it under the terms of the GNU Lesser General Public License as published by
12 * the Free Software Foundation, either version 3 of the License, or
13 * (at your option) any later version.
14 *
15 * wiringPi is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU Lesser General Public License for more details.
19 *
20 * You should have received a copy of the GNU Lesser General Public License
21 * along with wiringPi. If not, see <http://www.gnu.org/licenses/>.
22 ***********************************************************************
23 */
24
25 #define LSBFIRST 0
26 #define MSBFIRST 1
27
28 #ifndef _STDINT_H
29 # include <stdint.h>
30 #endif
31
32 #ifdef __cplusplus
33 extern "C" {
34 #endif
35
36 extern uint8_t shiftIn (uint8_t dPin, uint8_t cPin, uint8_t order) ;
37 extern void shiftOut (uint8_t dPin, uint8_t cPin, uint8_t order, uint8_t val) ;
38
39 #ifdef __cplusplus
40 }
41 #endif
74HC595.C
1 /*
2 * wiringShift.c:
3 * Emulate some of the Arduino wiring functionality.
4 *
5 * Copyright (c) 2009-2012 Gordon Henderson.
6 ***********************************************************************
7 * This file is part of wiringPi:
8 * https://projects.drogon.net/raspberry-pi/wiringpi/
9 *
10 * wiringPi is free software: you can redistribute it and/or modify
11 * it under the terms of the GNU Lesser General Public License as published by
12 * the Free Software Foundation, either version 3 of the License, or
13 * (at your option) any later version.
14 *
15 * wiringPi is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU Lesser General Public License for more details.
19 *
20 * You should have received a copy of the GNU Lesser General Public License
21 * along with wiringPi. If not, see <http://www.gnu.org/licenses/>.
22 ***********************************************************************
23 */
24
25 #include <stdint.h>
26 #include "wiringPi.h"
27 #include "wiringShift.h"
28
29 /*
30 * shiftIn:
31 * Shift data in from a clocked source
32 *********************************************************************************
33 */
34
35 uint8_t shiftIn (uint8_t dPin, uint8_t cPin, uint8_t order)
36 {
37 uint8_t value = 0 ;
38 int8_t i ;
39
40 if (order == MSBFIRST)
41 for (i = 7 ; i >= 0 ; --i)
42 {
43 digitalWrite (cPin, HIGH) ;
44 value |= digitalRead (dPin) << i ;
45 digitalWrite (cPin, LOW) ;
46 }
47 else
48 for (i = 0 ; i < 8 ; ++i)
49 {
50 digitalWrite (cPin, HIGH) ;
51 value |= digitalRead (dPin) << i ;
52 digitalWrite (cPin, LOW) ;
53 }
54
55 return value;
56 }
57
58 /*
59 * shiftOut:
60 * Shift data out to a clocked source
61 *********************************************************************************
62 */
63 void shiftOut (uint8_t dPin, uint8_t cPin, uint8_t order, uint8_t val)
64 {
65 int8_t i;
66 if (order == MSBFIRST)
67 for (i = 7 ; i >= 0 ; --i)
68 {
69 digitalWrite (dPin, val & (1 << i)) ;
70 digitalWrite (cPin, HIGH) ;
71 digitalWrite (cPin, LOW) ;
72 }
73 else
74 for (i = 0 ; i < 8 ; ++i)
75 {
76 digitalWrite (dPin, val & (1 << i)) ;
77 digitalWrite (cPin, HIGH) ;
78 digitalWrite (cPin, LOW) ;
79 }
80 }
时间： 2024-12-24 16:27:00