前言

本章结合之前的hx711驱动，实现读取质量，记录时间及剩余质量并存入csv文件，计算质量差并总计。

代码

luckfox-pico\project\app\test_app\hx711\hx711_app_addtime.c

#include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>
#include <unistd.h>
// #include <linux/delay.h>
#include <sys/time.h>
#include <string.h>
#include <time.h>#define IIO_DEVICE "/sys/bus/iio/devices/iio:device0"
#define SENSOR_CALI_PATH_OFFSET "/root/hx711_cal_offset"
#define SENSOR_CALI_PATH_SCALE "/root/hx711_cal_scale"static int cal_offset = 8500000;    // save raw value without test itemsstatic int cal_scale = 475;         // when set phone, 1g is 475
static int cal_weight = 187;  // the weight of phone// static float weight = 0;
static int weight = 0;//--------------- hx711 value process ---------------
#define LIST_NUM_MAX 64
#define CSV_PATH "/root/hx711.csv"int v1,v2;
int flag_change;struct weight_data{int weight;time_t time;
};struct weight_data list[LIST_NUM_MAX];
int current_list_num=0;int drink_water=0;//--------------- hx711 value process ---------------// float convert_to_weight(int sensor_data) {
int convert_to_weight(int sensor_data) {int weight;// weight = (float)(sensor_data - cal_offset) / cal_scale;// printf("\nsensor_raw=%d,cal_offset=%d,cal_scale=%d\n",sensor_data,cal_offset,cal_scale);if(cal_scale != 0)weight = (sensor_data - cal_offset) / cal_scale;elseweight = 0;// printf("Sensor data: %.1f\n", weight);// printf("Sensor data: %d\n", weight);return weight;
}int get_hx711_raw(){int fd;char buf[64];ssize_t num_read;fd = open(IIO_DEVICE "/in_voltage0_raw", O_RDONLY);if (fd < 0) {perror("Failed to open iio device");return 1;}num_read = read(fd, buf, sizeof(buf) - 1);if (num_read < 0) {perror("Failed to read sensor data");close(fd);return 1;}close(fd);buf[num_read] = '\0';int sensor_data = atoi(buf);// printf("  raw sensor_data=%d\n",sensor_data);return sensor_data;
}// float get_hx711_value(){
int get_hx711_value(){int sensor_data = get_hx711_raw();weight = convert_to_weight(sensor_data);return weight;
}// save scale&offset to file 
void set_cal_value(){int fd;char tmp_char[64];fd = open(SENSOR_CALI_PATH_OFFSET, O_CREAT|O_RDWR ,0777);if (fd < 0) {perror("Failed to open cal offset.");return;}// printf("-------\ncal_offset=%d\n",cal_offset);memset(tmp_char,0,sizeof(tmp_char));sprintf(tmp_char,"%d\0",cal_offset);// printf("xxx tmp_char=[%s]\n",tmp_char);write(fd, tmp_char, sizeof(tmp_char));close(fd);fd = open(SENSOR_CALI_PATH_SCALE, O_CREAT|O_RDWR ,0777);if (fd < 0) {perror("Failed to open cal offset.");return;}// printf("cal_scale=%d\n",cal_scale);memset(tmp_char,0,sizeof(tmp_char));sprintf(tmp_char,"%d\0",cal_scale) ;// printf("xxx tmp_char=[%s]\n-------\n",tmp_char);write(fd, tmp_char, sizeof(tmp_char)-1);close(fd);
}void print_cal_value_and_raw(int sensor_raw_tmp){printf("cal&raw:\n");printf("   cal_offset=%d sensor_raw=%d\n", cal_offset, sensor_raw_tmp);printf("   test_offset\t%d\n   cal_weight\t%d\n   cal_scale\t%d\n",sensor_raw_tmp - cal_offset, cal_weight, cal_scale);printf("\n");
}void print_cal_value(){printf("hx711 calibration value\n");printf("   cal_offset\t%d\n   cal_weight\t%d\n   cal_scale\t%d\n",cal_offset, cal_weight, cal_scale);printf("\n");
}void sns_calibration(){int cal_test_num = 10;int cal_average = 0;int cal_test_tmp = 0;int cal_scale_raw = 0;// test 10 times to get offset averagefor(int i=0; i<cal_test_num; i++){cal_test_tmp = get_hx711_raw();usleep(10);cal_average = (cal_average * i + cal_test_tmp)/(i+1);}cal_offset=cal_average;usleep(20);printf("!!! Please put test items on the board whose weight same with cmd3\nWaiting input char to continue ...\n");getchar();cal_test_tmp = get_hx711_raw();cal_scale_raw = cal_test_tmp - cal_offset;cal_scale = (cal_scale_raw)/cal_weight;print_cal_value_and_raw(cal_test_tmp);set_cal_value();
}void get_cal_value(){int tmp_offset;int tmp_scale;char tmp_file_value[64];int fd;// printf("get_cal_value\n");fd = open(SENSOR_CALI_PATH_OFFSET, O_RDWR,0777);if (fd < 0) {perror("Failed to open cal offset.");return;}read(fd, tmp_file_value, sizeof(tmp_file_value) - 1);// printf("tmp_file_value=%s\n",tmp_file_value);tmp_offset = atoi(tmp_file_value);// printf("tmp_offset=%d\n",tmp_offset);close(fd);fd = open(SENSOR_CALI_PATH_SCALE, O_RDWR,0777);if (fd < 0) {perror("Failed to open cal offset.");return;}memset(tmp_file_value,0,sizeof(tmp_file_value));read(fd, tmp_file_value, sizeof(tmp_file_value) - 1);tmp_scale = atoi(tmp_file_value);// printf("tmp_offset=%d\n",tmp_scale);close(fd);cal_offset = tmp_offset;cal_scale = tmp_scale;
}#define LEN_MAX 30void save_to_csv(struct weight_data value)
{char tmp_c[LEN_MAX];char * tmp;FILE *fp = fopen(CSV_PATH, "a+");if (fp == NULL) {fprintf(stderr, "fopen() failed.\n");exit(EXIT_FAILURE);}struct tm *tm_t;tm_t = localtime(&value.time);strftime(tmp_c,LEN_MAX,"%F %T",tm_t);printf("time：%s\t",tmp_c);fprintf(fp, tmp_c);fprintf(fp, " | ");memset(tmp_c,0,LEN_MAX);sprintf(tmp_c, "%d", value.weight);printf("weight：%s\n",tmp_c);fprintf(fp, tmp_c);fprintf(fp, "\n");fclose(fp);
}int value_changed(int value1, int value2)
{if(value1 != value2){flag_change = 1;// printf("change value v1=%d  v2=%d\n",value1,value2);}else{if(flag_change == 1 && value1 != 0){// save value// printf("change value %d\n",value1);list[current_list_num].weight = value1;// printf("change value %d\n",list[current_list_num].weight);// save timetime_t tnow = time(0);// printf("当前时间为：%ld\r\n",tnow);list[current_list_num].time = tnow;if(list[current_list_num].weight < list[current_list_num-1].weight){drink_water = drink_water + list[current_list_num-1].weight - list[current_list_num].weight;printf("== drink %dmL\n",drink_water);}// save value to filesave_to_csv(list[current_list_num]);current_list_num++;flag_change = 0;}}return flag_change;
}int get_value()
{int value = 0;// get valuevalue = get_hx711_value();// save value to v1&v2v1 = v2;v2 = value;// judgevalue_changed(v1,v2);return value;
}int main(int argc, char *argv[]) {char cmd1[16];char cmd2[16];char cmd3[16];int ret;int val_tmp=0;// calibration: put the items whose weight is known. weight sends to cmd3// ./hx771_app -c 187if(argc == 3){strcpy(cmd2,argv[1]);strcpy(cmd3,argv[2]);printf("cmd2=%s cmd3=%s\n",cmd2,cmd3);if(strcmp(cmd2, "-c") == 0){printf("get cal cal_weight %s\n",cmd3);cal_weight=atoi(cmd3);        // save the weight of cal items} else {printf("hx711 no cal_weight\n");return 0;}sns_calibration();sleep(1);// test the calibration resultval_tmp = get_hx711_value();printf("sensor value: %d\n", val_tmp);return 0;}printf("-------------test-------------\n");get_cal_value();print_cal_value();int sensor_data;while(1){// val_tmp = get_hx711_value();val_tmp = get_value();// if(val_tmp != 0)//     printf("%02d: %d\n",50 - test_num,val_tmp);sleep(1);}printf("--------------------------\n");return 0;
}

编译

luckfox-pico\project\app\test_app\hx711\build.sh

export PATH=/home/youkai/0_pro/luckfox/luckfox-pico/tools/linux/toolchain/arm-rockchip830-linux-uclibcgnueabihf/bin:$PATH
source ~/.bashrc  
cd ~/0_pro/luckfox/luckfox-pico/project/app/test_app/hx711
arm-rockchip830-linux-uclibcgnueabihf-gcc hx711_app_addtime.c -o hx711_app_addtime

运行

运行bat可以进行快速测试，放在windows本地

time_get_hx711.bat

scp youkai@192.168.206.130:/home/youkai/0_pro/luckfox/luckfox-pico/project/app/test_app/hx711/hx711_app_addtime .adb push hx711_app_addtime /root/
adb shell "chmod 777 /root/hx711_app_addtime"
adb shell "./root/hx711_app_addtime"

结果

代码实现了测试重量，并计算出喝水的毫升数。

读取保存的时间和重量。

# cat hx711.csv
2023-11-15 19:42:55 | 68
2023-11-15 19:43:07 | 194
2023-11-15 19:43:14 | 3
2023-11-15 19:43:27 | 68
2023-11-15 19:43:38 | 10