HomeEnergyMeter/main/uart.c

#include <stdio.h>
#include <string.h>
#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "freertos/queue.h"
#include "driver/uart.h"
#include "esp_log.h"
#include "config.h"

#include "uart.h"

#ifdef SERIAL_ENABLED

/************************************************************************************************
 * On the ESP-WROOM-32 Card, the UART2-Pins are avaialable.
 * TXD: GPIO17
 * RXD: GPIO16
 * https://www.espressif.com/sites/default/files/documentation/esp32-wroom-32_datasheet_en.pdf
 * http://esp32.net/images/MH-ET-LIVE/ESP32-DevKit/MH-ET-LIVE_ESP32-DevKit_DiagramPinout.png
 * https://i.imgur.com/ctokhuk.jpg (Schematic of the MH-ET-LIVE)
 * 
 ************************************************************************************************/
#define UART_NUMBER UART_NUM_2

void initUart() {
    
    uart_config_t uart_config = {
        .baud_rate = 19200,
        .data_bits = UART_DATA_8_BITS,
        .parity = UART_PARITY_DISABLE,
        .stop_bits = UART_STOP_BITS_1,
        .flow_ctrl = UART_HW_FLOWCTRL_DISABLE,
    };
    ESP_ERROR_CHECK(uart_param_config(UART_NUMBER, &uart_config));

    ESP_ERROR_CHECK(uart_set_pin(UART_NUMBER, UART_TX_PIN, UART_RX_PIN, UART_PIN_NO_CHANGE, UART_PIN_NO_CHANGE));

    const int uart_buffer_size = (1024 * 2);
    QueueHandle_t uart_queue;
    ESP_ERROR_CHECK(uart_driver_install(UART_NUMBER, uart_buffer_size, uart_buffer_size, 10, &uart_queue, 0));
}



unsigned char serialRead(void) {
    unsigned char data;
    const int length = uart_read_bytes(UART_NUMBER, (uint8_t*)&data, 1, 0);
    if( length > 0 )
        return data;
    else
        return '\0';
}

int serialAvailable() {
    size_t size;
    uart_get_buffered_data_len(UART_NUMBER, &size);
    return (size == 0)? 0 : 1;
}

void writeUARTData(const char *str) {
    uart_tx_chars(UART_NUMBER, (const char*)str, strlen(str));
}

void readData() {
    uint8_t data[2048];
    int length = 0;
    printf("readData()a\n");
    ESP_ERROR_CHECK(uart_get_buffered_data_len(UART_NUMBER, (size_t*)&length));
    printf("readData()b  %d\n",length);
    length = uart_read_bytes(UART_NUMBER, data, length, 100);
    printf("readData()c  %d\n",length);
    data[length] = '\0';

    printf("Read:%d :%s\n",length,(char *)data);
}

#endif