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pcf8523 rtc esp32
#include <apps/sntp/sntp.h>
#include <driver/i2c.h>
#include <esp_log.h>
#include <freertos/FreeRTOS.h>
#include <freertos/task.h>
#include <lwip/sockets.h>
#include <stdio.h>
#include <time.h>
#include "errorhandle_func.h"
#include "sdkconfig.h"
#define SDA_PIN 23
#define SCL_PIN 22
#define RTC_ADDRESS 0x68 // most I2C rtcs have their address on 0x68. any doubt check with i2c scanner snippet
static char tag[] = "RTC";
static uint8_t intToBCD(uint8_t num) {
return ((num / 10) << 4) | (num%10);
}
static uint8_t bcdToInt(uint8_t bcd) {
// 0x10
return ((bcd >> 4) * 10) + (bcd & 0x0f);;
}
void initI2C() {
i2c_config_t conf;
conf.mode = I2C_MODE_MASTER;
conf.sda_io_num = SDA_PIN;
conf.scl_io_num = SCL_PIN;
conf.sda_pullup_en = GPIO_PULLUP_ENABLE;
conf.scl_pullup_en = GPIO_PULLUP_ENABLE;
conf.master.clk_speed = 100000;
ESP_ERROR_CHECK(i2c_param_config(I2C_NUM_0, &conf));
ESP_ERROR_CHECK(i2c_driver_install(I2C_NUM_0, I2C_MODE_MASTER, 0, 0, 0));
}
/*
* PCF8523 slightly changed its 7 bytes encoded in BCD:
* 03h - Seconds - 00-59
* 04h - Minutes - 00-59
* 05h - Hours - 00-23
* 06h - monthday - 01-31
* 07h - weekday - 00-06
* 08h - Month - 01-12
* 09h - Year - 00-99
*
*/
time_t rtc_readValue() {
i2c_cmd_handle_t cmd = i2c_cmd_link_create();
ESP_ERROR_CHECK(i2c_master_start(cmd));
ESP_ERROR_CHECK(i2c_master_write_byte(cmd, (RTC_ADDRESS << 1) | I2C_MASTER_WRITE, true /* expect ack */));
ESP_ERROR_CHECK(i2c_master_write_byte(cmd, 0x03, 1)); // start address
ESP_ERROR_CHECK(i2c_master_start(cmd));
ESP_ERROR_CHECK(i2c_master_write_byte(cmd, (RTC_ADDRESS << 1) | I2C_MASTER_READ, true /* expect ack */));
uint8_t data[7];
ESP_ERROR_CHECK(i2c_master_read(cmd, data, 7, false));
ESP_ERROR_CHECK(i2c_master_stop(cmd));
COMMANDCHECKOKERR(i2c_master_cmd_begin(I2C_NUM_0, cmd, 1000/portTICK_PERIOD_MS),"RTC COMMAND");
i2c_cmd_link_delete(cmd);
int i;
for (i=0; i<7; i++) {
ESP_LOGD(tag, "%d: 0x%.2x", i, data[i]);
}
struct tm tm;
tm.tm_sec = bcdToInt(data[0]);
tm.tm_min = bcdToInt(data[1]);
tm.tm_hour = bcdToInt(data[2]);
tm.tm_mday = bcdToInt(data[3]);
tm.tm_mon = bcdToInt(data[5]) - 1; // 0-11 - Note: The month on the PCF8523 is 1-12.
tm.tm_year = bcdToInt(data[6]) + 100; // Years since 1900
time_t readTime = mktime(&tm);
return readTime;
}
void rtc_writeValue(time_t newTime) {
ESP_LOGD(tag, ">> writeValue: %ld", newTime);
struct tm tm;
gmtime_r(&newTime, &tm);
char buf[30];
ESP_LOGD(tag, " - %s", asctime_r(&tm, buf));
esp_err_t errRc;
i2c_cmd_handle_t cmd = i2c_cmd_link_create();
ESP_ERROR_CHECK(i2c_master_start(cmd));
ESP_ERROR_CHECK(i2c_master_write_byte(cmd, (RTC_ADDRESS << 1) | I2C_MASTER_WRITE, 1 /* expect ack */));
ESP_ERROR_CHECK(i2c_master_write_byte(cmd, 0x03, 1));
ESP_ERROR_CHECK(i2c_master_write_byte(cmd, intToBCD(tm.tm_sec), 1)); // seconds
ESP_ERROR_CHECK(i2c_master_write_byte(cmd, intToBCD(tm.tm_min), 1 )); // minutes
ESP_ERROR_CHECK(i2c_master_write_byte(cmd, intToBCD(tm.tm_hour), 1 )); // hours
ESP_ERROR_CHECK(i2c_master_write_byte(cmd, intToBCD(tm.tm_mday), 1)); // date of month
ESP_ERROR_CHECK(i2c_master_write_byte(cmd, intToBCD(tm.tm_wday+1), 1 )); // week day
ESP_ERROR_CHECK(i2c_master_write_byte(cmd, intToBCD(tm.tm_mon+1), 1)); // month
ESP_ERROR_CHECK(i2c_master_write_byte(cmd, intToBCD(tm.tm_year-100), 1)); // year
ESP_ERROR_CHECK(i2c_master_stop(cmd));
errRc = i2c_master_cmd_begin(I2C_NUM_0, cmd, 1000/portTICK_PERIOD_MS);
if (errRc != 0) {
ESP_LOGE(tag, "i2c_master_cmd_begin: %d", errRc);
}
i2c_cmd_link_delete(cmd);
}
/*
implement in your time function
@Kolban created a nice one, here is my contribution.
esp_err_t sntp_update(){
static const char *tag = "TIME_SETUP";
esp_err_t ret;
char buffer[20];
EventBits_t bitreturn;
TickType_t waittime = 10000/portTICK_PERIOD_MS;
bitreturn = xEventGroupWaitBits(event_group, WIFI_CONNECTED_BIT, pdFALSE, pdTRUE, waittime);
if((bitreturn & BIT0) != 0){
printf("going online\n");
}
else printf("going offline\n");
// initialize the SNTP service
sntp_setoperatingmode(SNTP_OPMODE_POLL);
// to create SNTP server variable make a #define statement i.e. "pool.ntp.org"
sntp_setservername(0, CONFIG_SNTP_SERVER);
sntp_init();
initI2C();
time_t t;
struct tm timertc;
t = rtc_readValue();
localtime_r(&t, &timertc);
strftime(buffer, sizeof(buffer), "%Y/%m/%d %H:%M:%S", &timertc);
ESP_LOGI(tag,"Current time in rtc (GTM) is: %s\n\n", buffer);
// wait for the service to set the time
time_t now;
struct tm timeinfo;
time(&now);
localtime_r(&now, &timeinfo);
int counter = 0;
// try for a minute to get time from network
while((timeinfo.tm_year < (2018 - 1900)) && (counter < 12))
{
ESP_LOGW(tag,"Time outdated, waiting...\n");
vTaskDelay(5000 / portTICK_PERIOD_MS);
time(&now);
localtime_r(&now, &timeinfo);
counter ++;
}
if((timeinfo.tm_year < (2018 - 1900)) && (counter == 12)){
ESP_LOGE(tag, "TIMEOUT");
// stick to rtc time
now = rtc_readValue();
}
else{
// update rtc time
rtc_writeValue(now);
}
// to create timezone variable make a #define statement i.e. "COT+5"
setenv("TZ",CONFIG_TIMEZONE_TZ, 1);
tzset();
// print the actual time in location
localtime_r(&now, &timeinfo);
strftime(buffer, sizeof(buffer), "%Y/%m/%d %H:%M:%S", &timeinfo);
ESP_LOGI(tag,"Current time in your Location: %s\n\n", buffer);
// check time set in rtc in case it was updated from network
t = rtc_readValue();
localtime_r(&t, &timertc);
strftime(buffer, sizeof(buffer), "%Y/%m/%d %H:%M:%S", &timertc);
ESP_LOGI(tag,"Current time in rtc (GTM) is: %s\n\n", buffer);
ret = ESP_OK;
return ret;
}
*/
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