Cubieboard1显示DS18B20温度信息到LED

cubieboard

Cubieboard1的内核已经支持w1温度传感器DS18B20 (依赖的内核选项和模块包括dallas's 1-wire support, gpio_sunxi, w1_sunxi, w1_gpio, w1_slave_therm )。 下图的DIY是在8位8段LED显示模块上同时显示当前时间和气温的实验。 jarry大侠在很久前的帖子(http://forum.cubietech.com/forum.php?mod=viewthread&tid=474)中介绍了DS18B20在cubieboard1上的使用，现在已经不需要打补丁或者另外编译内核模块了。只要按内核配置的说明改好script.bin即可： 本例中的script.fex相关设置如下： [gpio_para] gpio_used = 1 gpio_num = 31 ... gpio_pin_28 = port:PB10<0><default><default><0> gpio_pin_29 = port:PB11<1><default><default><default> gpio_pin_30 = port:PB13<1><default><default><default> gpio_pin_31 = port:PH07<1><default><default><default> [w1_para] gpio = 28 [color=rgb(46, 166, 255) !important]复制代码 最后是本例的C代码 #include <stdio.h> #include <stdlib.h> #include <string.h> #include <time.h> #include <signal.h> #include <pthread.h> #include "gpio_lib.h" #define LSBFIRST 0 #define MSBFIRST 1 #define  DISPBUF_LEN 8 typedef unsigned char byte; // w1-thermal(DS18B20) device file, change it in your case. const char* DS18B20_DEVICE="/sys/bus/w1/devices/28-000004f0230d/w1_slave"; /* * 74HC595 relative stuff */ // Cubieboard pin connected to ST_CP of 74HC595 (RCK) unsigned int latchPin = SUNXI_GPB(11); // Cubieboard pin connected to SH_CP of 74HC595 (SCK) unsigned int clockPin = SUNXI_GPB(13); // Cubieboard pin connected to DS of 74HC595 (DIN) unsigned int dataPin = SUNXI_GPH(7); /* * Display relative stuff */ // Digits: "0,1,2,....,9" for common anode 8-segment-LED unsigned int digit_tab[] = { 0xc0, 0xf9, 0xa4, 0xb0, 0x99, 0x92,                         0x82, 0xf8, 0x80, 0x90}; // Digits with a 'dot' at the right-bottom corner unsigned int digitdot_tab[] = { 0xc0&0x7f, 0xf9&0x7f, 0xa4&0x7f,                         0xb0&0x7f, 0x99&0x7f, 0x92&0x7f, 0x82&0x7f,                         0xf8&0x7f, 0x80&0x7f, 0x90&0x7f}; // Symbols: 'clear', 'dot', '-' unsigned int symbol_tab[]={ 0xff, 0x7f, 0xbf}; // LED display buffer static char dispbuf[DISPBUF_LEN]; /** * Set Cubieboard's GPIO port-D pin I/O mode: INPUT/OUTPUT */ void pinMode(unsigned int pin, unsigned int io_mode) {     if (SETUP_OK != sunxi_gpio_set_cfgpin(pin, io_mode))     {         printf("Failed to config GPIO pin\n");     } } /** * Set Cubieboard's GPIO port-D pin value(LOW/HIGH) */ void digitalWrite(int pin, int hl) {     if (sunxi_gpio_output(pin, hl))     {         printf("Failed to set GPIO pin value\n");     } } /** * Arduino shiftOut: * https://github.com/arduino/Ardui ... uino/wiring_shift.c */ void shiftOut(unsigned int dataPin, unsigned int clockPin, int bitOrder, byte val) {     byte i;     for (i = 0; i < 8; i++)     {         if (bitOrder == LSBFIRST)             digitalWrite(dataPin, ! !(val & (1 << i)));         else             digitalWrite(dataPin, ! !(val & (1 << (7 - i))));         digitalWrite(clockPin, HIGH);         digitalWrite(clockPin, LOW);     } } /** * Initialize the GPIO & relative pins */ void init_gpio() {     if (SETUP_OK != sunxi_gpio_init())     {         printf("Failed to initialize GPIO\n");     }     pinMode(latchPin, OUTPUT);     pinMode(clockPin, OUTPUT);     pinMode(dataPin, OUTPUT); } /** * Get current temperature from the w1-thermal device */ void get_temperature(char* tempbuf, int len) {     FILE* fp=fopen(DS18B20_DEVICE,"r");     char* line=NULL;     char* temperature_tok=NULL;     int temperature=0;     int n;     if(!fp){         fprintf(stderr,"Failed to open device(%s) file!\n", DS18B20_DEVICE);         return;     }     // skip the first line     getline(&line, &n, fp);     free(line);     line=NULL;     // get the temperature line     getline(&line, &n, fp);     strtok(line,"=");     temperature_tok=strtok(NULL,"\n");     strncpy(tempbuf, temperature_tok, len);     free(line);     fclose(fp); } /** * Thread of filling the time infomation into display buffer */ void* time_to_dispbuf() {     time_t timep;     struct tm *p;     char timebuf[4];     int interval=1; // in seconds     while(1){         // get localtime         time(&timep);         p = localtime(&timep);         sprintf(timebuf, "%02d%02d", p->tm_hour, p->tm_min);         dispbuf[0]=digit_tab[timebuf[0] - '0'];         dispbuf[1]=digitdot_tab[timebuf[1] - '0'];         dispbuf[2]=digit_tab[timebuf[2] - '0'];         dispbuf[3]=digit_tab[timebuf[3] - '0'];         dispbuf[4]=symbol_tab[2]; // '-'         sleep(interval);     } } /** * Thread of filling the temperature into display buffer */ void* temp_to_dispbuf() {     char tempbuf[3];     int interval=5; // in seconds;     while(1){         get_temperature(tempbuf, sizeof tempbuf);         dispbuf[5]=digit_tab[tempbuf[0]-'0'];         dispbuf[6]=digitdot_tab[tempbuf[1]-'0'];         dispbuf[7]=digit_tab[tempbuf[2]-'0'];         sleep(interval);     } } int main(int argc, char **argv) {     pthread_t get_time_thread, get_temp_thread;     void * thread_ret;     init_gpio();     pthread_create( &get_time_thread, NULL, time_to_dispbuf, NULL);     pthread_create( &get_temp_thread, NULL, temp_to_dispbuf, NULL);     while (1)     {         int i;         for(i=0;i<DISPBUF_LEN;i++){             digitalWrite(latchPin, 0);             shiftOut(dataPin, clockPin, MSBFIRST, 1<<i);             shiftOut(dataPin, clockPin, MSBFIRST, dispbuf);             digitalWrite(latchPin, 1);             usleep(2000);         }     }     pthread_join(get_time_thread,&thread_ret);     pthread_join(get_temp_thread,&thread_ret);     return 0; } [color=rgb(46, 166, 255) !important]复制代码

原文作者：soloforce
原文链接：http://forum.cubietech.com/forum ... 1545&extra=page%3D1

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