wifi working

.gitignore

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+Kconfig.projbuild
+build
+sdkconfig
+sdkconfig.old
+wifi_cfg.h
+config.h

.gitmodules

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+[submodule "components/u8g2"]
+	path = components/u8g2
+	url = git@github.com:olikraus/u8g2.git

CMakeLists.txt

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+# The following lines of boilerplate have to be in your project's
+# CMakeLists in this exact order for cmake to work correctly
+cmake_minimum_required(VERSION 3.5)
+
+include($ENV{IDF_PATH}/tools/cmake/project.cmake)
+project(esp32-wallet-viewer)

Makefile

@@ -0,0 +1,9 @@
+#
+# This is a project Makefile. It is assumed the directory this Makefile resides in is a
+# project subdirectory.
+#
+
+PROJECT_NAME := esp32-wallet-viewer
+
+include $(IDF_PATH)/make/project.mk
+

README.md

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+# esp32-wallet-viewer
+esp32 code to monitor wallets
+
+![img01](https://raw.githubusercontent.com/arnaucube/esp32-wallet-viewer/master/img01.png 'img01')
+
+- `main/wifi_cfg.h` example:
+```c
+#define WIFI_SSID "wifi name"
+#define WIFI_PASS "password"
+```
+
+- get `u8g2` submodule:
+```
+git submodule init
+```
+
+- run:
+```
+> make
+
+> make flash
+```
+
+---
+
+- Helpful esp32 documentation: https://docs.espressif.com/projects/esp-idf/en/latest/get-started/
+- Helpful esp32 examples: https://github.com/lucadentella/esp32-tutorial

components/u8g2

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+Subproject commit 45ac4e0edc76c6bc3d808304fccb73c543535ded

main/CMakeLists.txt

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+set(COMPONENT_SRCS "main.c")
+set(COMPONENT_ADD_INCLUDEDIRS "")
+
+register_component()

main/component.mk

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+#
+# "main" pseudo-component makefile.
+#
+# (Uses default behaviour of compiling all source files in directory, adding 'include' to include path.)
+

main/main.c

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+#include <stdio.h>
+#include <string.h>
+
+#include "freertos/FreeRTOS.h"
+#include "freertos/task.h"
+#include "freertos/event_groups.h"
+#include "esp_system.h"
+#include "esp_spi_flash.h"
+
+#include "u8g2_esp32_hal.h"
+
+#include "esp_wifi.h"
+#include "esp_event_loop.h"
+#include "esp_log.h"
+#include "nvs_flash.h"
+
+#include "lwip/netdb.h"
+#include "lwip/sockets.h"
+
+#include "config.h"
+
+
+#define PIN_SDA 5
+#define PIN_SCL 4
+
+static u8g2_t u8g2;
+
+// Event group
+static EventGroupHandle_t wifi_event_group;
+const int CONNECTED_BIT = BIT0;
+
+static void print_screen(char *s1, char *s2, char *s3);
+
+// HTTP request
+static const char *REQUEST = "GET "CONFIG_PATH" HTTP/1.1\n"
+	"Host: "CONFIG_URL"\n"
+	"User-Agent: ESP32\n"
+	"\n";
+
+static void print_screen(char *s1, char *s2, char *s3)
+{
+	u8g2_ClearBuffer(&u8g2);
+	u8g2_DrawStr(&u8g2, 2,17,s1);
+	u8g2_DrawStr(&u8g2, 2,37,s2);
+	u8g2_DrawStr(&u8g2, 2,57,s3);
+	u8g2_SendBuffer(&u8g2);
+	vTaskDelay(300 / portTICK_RATE_MS);
+}
+
+// Wifi event handler
+static esp_err_t event_handler(void *ctx, system_event_t *event)
+{
+	switch(event->event_id) {
+	case SYSTEM_EVENT_STA_START:
+		esp_wifi_connect();
+		break;
+	case SYSTEM_EVENT_STA_GOT_IP:
+		xEventGroupSetBits(wifi_event_group, CONNECTED_BIT);
+		break;
+	case SYSTEM_EVENT_STA_DISCONNECTED:
+		xEventGroupClearBits(wifi_event_group, CONNECTED_BIT);
+		break;
+	default:
+		break;
+	}
+	return ESP_OK;
+}
+
+// Main task
+void main_task(void *pvParameter)
+{
+	// wait for connection
+	xEventGroupWaitBits(wifi_event_group, CONNECTED_BIT, false, true, portMAX_DELAY);
+	printf("connected!\n");
+	print_screen("wifi connected", "", "");
+	printf("\n");
+	
+	// print the local IP address
+	tcpip_adapter_ip_info_t ip_info;
+	ESP_ERROR_CHECK(tcpip_adapter_get_ip_info(TCPIP_ADAPTER_IF_STA, &ip_info));
+	printf("IP Address:  %s\n", ip4addr_ntoa(&ip_info.ip));
+	printf("Subnet mask: %s\n", ip4addr_ntoa(&ip_info.netmask));
+	printf("Gateway:     %s\n", ip4addr_ntoa(&ip_info.gw));
+	printf("\n");
+	print_screen("IP Address:", ip4addr_ntoa(&ip_info.ip), "");
+	
+	// define connection parameters
+	const struct addrinfo hints = {
+		.ai_family = AF_INET,
+		.ai_socktype = SOCK_STREAM,
+	};
+	
+	// address info struct and receive buffer
+	struct addrinfo *res;
+	char recv_buf[100];
+	
+	// resolve the IP of the target website
+	int result = getaddrinfo(CONFIG_URL, CONFIG_PORT, &hints, &res);
+	if((result != 0) || (res == NULL)) {
+		printf("Unable to resolve IP for target website %s\n", CONFIG_URL);
+		while(1) vTaskDelay(1000 / portTICK_RATE_MS);
+	}
+	printf("Target website's IP resolved\n");
+	
+	// create a new socket
+	int s = socket(res->ai_family, res->ai_socktype, 0);
+	if(s < 0) {
+		printf("Unable to allocate a new socket\n");
+		while(1) vTaskDelay(1000 / portTICK_RATE_MS);
+	}
+	printf("Socket allocated, id=%d\n", s);
+	
+	// connect to the specified server
+	result = connect(s, res->ai_addr, res->ai_addrlen);
+	if(result != 0) {
+		printf("Unable to connect to the target website\n");
+		close(s);
+		while(1) vTaskDelay(1000 / portTICK_RATE_MS);
+	}
+	printf("Connected to the target website\n");
+	print_screen("Connected to the", "target website","");
+	
+	// send the request
+	result = write(s, REQUEST, strlen(REQUEST));
+		if(result < 0) {
+		printf("Unable to send the HTTP request\n");
+		close(s);
+		while(1) vTaskDelay(1000 / portTICK_RATE_MS);
+	}
+	printf("HTTP request sent\n");
+	print_screen("http request", "", "");
+	
+	// print the response
+	printf("HTTP response:\n");
+	printf("--------------------------------------------------------------------------------\n");
+	int r;
+	do {
+		bzero(recv_buf, sizeof(recv_buf));
+		r = read(s, recv_buf, sizeof(recv_buf) - 1);
+		for(int i = 0; i < r; i++) {
+			putchar(recv_buf[i]);
+		}
+	} while(r > 0);	
+	printf("--------------------------------------------------------------------------------\n");
+
+	close(s);
+	printf("Socket closed\n");
+	
+	while(1) {
+		vTaskDelay(5000 / portTICK_RATE_MS);
+	}
+}
+
+void app_main() {
+
+	// initialize the u8g2 hal
+	u8g2_esp32_hal_t u8g2_esp32_hal = U8G2_ESP32_HAL_DEFAULT;
+	u8g2_esp32_hal.sda = PIN_SDA;
+	u8g2_esp32_hal.scl = PIN_SCL;
+	u8g2_esp32_hal_init(u8g2_esp32_hal);
+
+	// initialize the u8g2 library
+	u8g2_Setup_ssd1306_i2c_128x64_noname_f(
+		&u8g2,
+		U8G2_R0,
+		u8g2_esp32_i2c_byte_cb,
+		u8g2_esp32_gpio_and_delay_cb);
+	
+	// set the display address
+	u8x8_SetI2CAddress(&u8g2.u8x8, 0x78);
+	
+	// initialize the display
+	u8g2_InitDisplay(&u8g2);
+	
+	// wake up the display
+	u8g2_SetPowerSave(&u8g2, 0);
+
+	// set font
+	u8g2_SetFont(&u8g2, u8g2_font_timR14_tf);
+
+	print_screen("screen ready", "", "");
+
+	// initialize NVS
+	ESP_ERROR_CHECK(nvs_flash_init());
+
+	// -- WIFI --
+	// disable the default wifi logging
+	esp_log_level_set("wifi", ESP_LOG_NONE);
+
+	// create the event group to handle wifi events
+	wifi_event_group = xEventGroupCreate();
+		
+	// initialize the tcp stack
+	tcpip_adapter_init();
+
+	// initialize the wifi event handler
+	ESP_ERROR_CHECK(esp_event_loop_init(event_handler, NULL));
+	
+	// initialize the wifi stack in STAtion mode with config in RAM
+	wifi_init_config_t wifi_init_config = WIFI_INIT_CONFIG_DEFAULT();
+	ESP_ERROR_CHECK(esp_wifi_init(&wifi_init_config));
+	ESP_ERROR_CHECK(esp_wifi_set_storage(WIFI_STORAGE_RAM));
+	ESP_ERROR_CHECK(esp_wifi_set_mode(WIFI_MODE_STA));
+
+	// configure the wifi connection and start the interface
+	wifi_config_t wifi_config = {
+		.sta = {
+		    .ssid = CONFIG_WIFI_SSID,
+		    .password = CONFIG_WIFI_PASS,
+		},
+	};
+	ESP_ERROR_CHECK(esp_wifi_set_config(ESP_IF_WIFI_STA, &wifi_config));
+	ESP_ERROR_CHECK(esp_wifi_start());
+	/* char buffer[50]; */
+	/* snprintf(buffer, sizeof(buffer), "Connecting to\n%s... ", CONFIG_WIFI_SSID); */
+	/* print_screen(buffer, "", ""); */
+	print_screen("Connectiong to:", CONFIG_WIFI_SSID, "");
+
+	// start the main task
+	xTaskCreate(&main_task, "main_task", 2048, NULL, 5, NULL);
+}

main/u8g2_esp32_hal.c

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+#include <stdio.h>
+#include <string.h>
+
+#include "sdkconfig.h"
+#include "esp_log.h"
+
+#include "freertos/FreeRTOS.h"
+#include "freertos/task.h"
+
+#include "u8g2_esp32_hal.h"
+
+static const char *TAG = "u8g2_hal";
+static const unsigned int I2C_TIMEOUT_MS = 1000;
+
+static spi_device_handle_t handle_spi;      // SPI handle.
+static i2c_cmd_handle_t    handle_i2c;      // I2C handle.
+static u8g2_esp32_hal_t    u8g2_esp32_hal;  // HAL state data.
+
+#undef ESP_ERROR_CHECK
+#define ESP_ERROR_CHECK(x)   do { esp_err_t rc = (x); if (rc != ESP_OK) { ESP_LOGE("err", "esp_err_t = %d", rc); assert(0 && #x);} } while(0);
+
+/*
+ * Initialze the ESP32 HAL.
+ */
+void u8g2_esp32_hal_init(u8g2_esp32_hal_t u8g2_esp32_hal_param) {
+	u8g2_esp32_hal = u8g2_esp32_hal_param;
+} // u8g2_esp32_hal_init
+
+/*
+ * HAL callback function as prescribed by the U8G2 library.  This callback is invoked
+ * to handle SPI communications.
+ */
+uint8_t u8g2_esp32_spi_byte_cb(u8x8_t *u8x8, uint8_t msg, uint8_t arg_int, void *arg_ptr) {
+	ESP_LOGD(TAG, "spi_byte_cb: Received a msg: %d, arg_int: %d, arg_ptr: %p", msg, arg_int, arg_ptr);
+	switch(msg) {
+		case U8X8_MSG_BYTE_SET_DC:
+			if (u8g2_esp32_hal.dc != U8G2_ESP32_HAL_UNDEFINED) {
+				gpio_set_level(u8g2_esp32_hal.dc, arg_int);
+			}
+			break;
+
+		case U8X8_MSG_BYTE_INIT: {
+			if (u8g2_esp32_hal.clk == U8G2_ESP32_HAL_UNDEFINED ||
+					u8g2_esp32_hal.mosi == U8G2_ESP32_HAL_UNDEFINED ||
+					u8g2_esp32_hal.cs == U8G2_ESP32_HAL_UNDEFINED) {
+				break;
+			}
+
+		  spi_bus_config_t bus_config;
+                  memset(&bus_config, 0, sizeof(spi_bus_config_t));
+		  bus_config.sclk_io_num   = u8g2_esp32_hal.clk; // CLK
+		  bus_config.mosi_io_num   = u8g2_esp32_hal.mosi; // MOSI
+		  bus_config.miso_io_num   = -1; // MISO
+		  bus_config.quadwp_io_num = -1; // Not used
+		  bus_config.quadhd_io_num = -1; // Not used
+		  //ESP_LOGI(TAG, "... Initializing bus.");
+		  ESP_ERROR_CHECK(spi_bus_initialize(HSPI_HOST, &bus_config, 1));
+
+		  spi_device_interface_config_t dev_config;
+		  dev_config.address_bits     = 0;
+		  dev_config.command_bits     = 0;
+		  dev_config.dummy_bits       = 0;
+		  dev_config.mode             = 0;
+		  dev_config.duty_cycle_pos   = 0;
+		  dev_config.cs_ena_posttrans = 0;
+		  dev_config.cs_ena_pretrans  = 0;
+		  dev_config.clock_speed_hz   = 10000;
+		  dev_config.spics_io_num     = u8g2_esp32_hal.cs;
+		  dev_config.flags            = 0;
+		  dev_config.queue_size       = 200;
+		  dev_config.pre_cb           = NULL;
+		  dev_config.post_cb          = NULL;
+		  //ESP_LOGI(TAG, "... Adding device bus.");
+		  ESP_ERROR_CHECK(spi_bus_add_device(HSPI_HOST, &dev_config, &handle_spi));
+
+		  break;
+		}
+
+		case U8X8_MSG_BYTE_SEND: {
+			spi_transaction_t trans_desc;
+			trans_desc.addr      = 0;
+			trans_desc.cmd   	 = 0;
+			trans_desc.flags     = 0;
+			trans_desc.length    = 8 * arg_int; // Number of bits NOT number of bytes.
+			trans_desc.rxlength  = 0;
+			trans_desc.tx_buffer = arg_ptr;
+			trans_desc.rx_buffer = NULL;
+
+			//ESP_LOGI(TAG, "... Transmitting %d bytes.", arg_int);
+			ESP_ERROR_CHECK(spi_device_transmit(handle_spi, &trans_desc));
+			break;
+		}
+	}
+	return 0;
+} // u8g2_esp32_spi_byte_cb
+
+/*
+ * HAL callback function as prescribed by the U8G2 library.  This callback is invoked
+ * to handle I2C communications.
+ */
+uint8_t u8g2_esp32_i2c_byte_cb(u8x8_t *u8x8, uint8_t msg, uint8_t arg_int, void *arg_ptr) {
+	ESP_LOGD(TAG, "i2c_cb: Received a msg: %d, arg_int: %d, arg_ptr: %p", msg, arg_int, arg_ptr);
+
+	switch(msg) {
+		case U8X8_MSG_BYTE_SET_DC: {
+			if (u8g2_esp32_hal.dc != U8G2_ESP32_HAL_UNDEFINED) {
+				gpio_set_level(u8g2_esp32_hal.dc, arg_int);
+			}
+			break;
+		}
+
+		case U8X8_MSG_BYTE_INIT: {
+			if (u8g2_esp32_hal.sda == U8G2_ESP32_HAL_UNDEFINED ||
+					u8g2_esp32_hal.scl == U8G2_ESP32_HAL_UNDEFINED) {
+				break;
+			}
+
+		    i2c_config_t conf;
+		    conf.mode = I2C_MODE_MASTER;
+			ESP_LOGI(TAG, "sda_io_num %d", u8g2_esp32_hal.sda);
+		    conf.sda_io_num = u8g2_esp32_hal.sda;
+		    conf.sda_pullup_en = GPIO_PULLUP_ENABLE;
+			ESP_LOGI(TAG, "scl_io_num %d", u8g2_esp32_hal.scl);
+		    conf.scl_io_num = u8g2_esp32_hal.scl;
+		    conf.scl_pullup_en = GPIO_PULLUP_ENABLE;
+			ESP_LOGI(TAG, "clk_speed %d", I2C_MASTER_FREQ_HZ);
+		    conf.master.clk_speed = I2C_MASTER_FREQ_HZ;
+			ESP_LOGI(TAG, "i2c_param_config %d", conf.mode);
+		    ESP_ERROR_CHECK(i2c_param_config(I2C_MASTER_NUM, &conf));
+			ESP_LOGI(TAG, "i2c_driver_install %d", I2C_MASTER_NUM);
+		    ESP_ERROR_CHECK(i2c_driver_install(I2C_MASTER_NUM, conf.mode, I2C_MASTER_RX_BUF_DISABLE, I2C_MASTER_TX_BUF_DISABLE, 0));
+			break;
+		}
+
+		case U8X8_MSG_BYTE_SEND: {
+			uint8_t* data_ptr = (uint8_t*)arg_ptr;
+			ESP_LOG_BUFFER_HEXDUMP(TAG, data_ptr, arg_int, ESP_LOG_VERBOSE);
+
+			while( arg_int > 0 ) {
+			   ESP_ERROR_CHECK(i2c_master_write_byte(handle_i2c, *data_ptr, ACK_CHECK_EN));
+			   data_ptr++;
+			   arg_int--;
+			}
+			break;
+		}
+
+		case U8X8_MSG_BYTE_START_TRANSFER: {
+			uint8_t i2c_address = u8x8_GetI2CAddress(u8x8);
+			handle_i2c = i2c_cmd_link_create();
+			ESP_LOGD(TAG, "Start I2C transfer to %02X.", i2c_address>>1);
+			ESP_ERROR_CHECK(i2c_master_start(handle_i2c));
+			ESP_ERROR_CHECK(i2c_master_write_byte(handle_i2c, i2c_address | I2C_MASTER_WRITE, ACK_CHECK_EN));
+			break;
+		}
+
+		case U8X8_MSG_BYTE_END_TRANSFER: {
+			ESP_LOGD(TAG, "End I2C transfer.");
+			ESP_ERROR_CHECK(i2c_master_stop(handle_i2c));
+			ESP_ERROR_CHECK(i2c_master_cmd_begin(I2C_MASTER_NUM, handle_i2c, I2C_TIMEOUT_MS / portTICK_RATE_MS));
+			i2c_cmd_link_delete(handle_i2c);
+			break;
+		}
+	}
+	return 0;
+} // u8g2_esp32_i2c_byte_cb
+
+/*
+ * HAL callback function as prescribed by the U8G2 library.  This callback is invoked
+ * to handle callbacks for GPIO and delay functions.
+ */
+uint8_t u8g2_esp32_gpio_and_delay_cb(u8x8_t *u8x8, uint8_t msg, uint8_t arg_int, void *arg_ptr) {
+	ESP_LOGD(TAG, "gpio_and_delay_cb: Received a msg: %d, arg_int: %d, arg_ptr: %p", msg, arg_int, arg_ptr);
+
+	switch(msg) {
+	// Initialize the GPIO and DELAY HAL functions.  If the pins for DC and RESET have been
+	// specified then we define those pins as GPIO outputs.
+		case U8X8_MSG_GPIO_AND_DELAY_INIT: {
+			uint64_t bitmask = 0;
+			if (u8g2_esp32_hal.dc != U8G2_ESP32_HAL_UNDEFINED) {
+				bitmask = bitmask | (1ull<<u8g2_esp32_hal.dc);
+			}
+			if (u8g2_esp32_hal.reset != U8G2_ESP32_HAL_UNDEFINED) {
+				bitmask = bitmask | (1ull<<u8g2_esp32_hal.reset);
+			}
+			if (u8g2_esp32_hal.cs != U8G2_ESP32_HAL_UNDEFINED) {
+				bitmask = bitmask | (1ull<<u8g2_esp32_hal.cs);
+			}
+
+            if (bitmask==0) {
+            	break;
+            }
+			gpio_config_t gpioConfig;
+			gpioConfig.pin_bit_mask = bitmask;
+			gpioConfig.mode         = GPIO_MODE_OUTPUT;
+			gpioConfig.pull_up_en   = GPIO_PULLUP_DISABLE;
+			gpioConfig.pull_down_en = GPIO_PULLDOWN_ENABLE;
+			gpioConfig.intr_type    = GPIO_INTR_DISABLE;
+			gpio_config(&gpioConfig);
+			break;
+		}
+
+	// Set the GPIO reset pin to the value passed in through arg_int.
+		case U8X8_MSG_GPIO_RESET:
+			if (u8g2_esp32_hal.reset != U8G2_ESP32_HAL_UNDEFINED) {
+				gpio_set_level(u8g2_esp32_hal.reset, arg_int);
+			}
+			break;
+	// Set the GPIO client select pin to the value passed in through arg_int.
+		case U8X8_MSG_GPIO_CS:
+			if (u8g2_esp32_hal.cs != U8G2_ESP32_HAL_UNDEFINED) {
+				gpio_set_level(u8g2_esp32_hal.cs, arg_int);
+			}
+			break;
+	// Set the Software I²C pin to the value passed in through arg_int.
+		case U8X8_MSG_GPIO_I2C_CLOCK:
+			if (u8g2_esp32_hal.scl != U8G2_ESP32_HAL_UNDEFINED) {
+				gpio_set_level(u8g2_esp32_hal.scl, arg_int);
+//				printf("%c",(arg_int==1?'C':'c'));
+			}
+			break;
+	// Set the Software I²C pin to the value passed in through arg_int.
+		case U8X8_MSG_GPIO_I2C_DATA:
+			if (u8g2_esp32_hal.sda != U8G2_ESP32_HAL_UNDEFINED) {
+				gpio_set_level(u8g2_esp32_hal.sda, arg_int);
+//				printf("%c",(arg_int==1?'D':'d'));
+			}
+			break;
+
+	// Delay for the number of milliseconds passed in through arg_int.
+		case U8X8_MSG_DELAY_MILLI:
+			vTaskDelay(arg_int/portTICK_PERIOD_MS);
+			break;
+	}
+	return 0;
+} // u8g2_esp32_gpio_and_delay_cb
+

main/u8g2_esp32_hal.h

@@ -0,0 +1,42 @@
+/*
+ * u8g2_esp32_hal.h
+ *
+ *  Created on: Feb 12, 2017
+ *      Author: kolban
+ */
+
+#ifndef U8G2_ESP32_HAL_H_
+#define U8G2_ESP32_HAL_H_
+#include "u8g2.h"
+
+#include "driver/gpio.h"
+#include "driver/spi_master.h"
+#include "driver/i2c.h"
+
+#define U8G2_ESP32_HAL_UNDEFINED (-1)
+
+#define I2C_MASTER_NUM I2C_NUM_1           //  I2C port number for master dev
+#define I2C_MASTER_TX_BUF_DISABLE   0      //  I2C master do not need buffer
+#define I2C_MASTER_RX_BUF_DISABLE   0      //  I2C master do not need buffer
+#define I2C_MASTER_FREQ_HZ          50000  //  I2C master clock frequency
+#define ACK_CHECK_EN   0x1                 //  I2C master will check ack from slave
+#define ACK_CHECK_DIS  0x0                 //  I2C master will not check ack from slave
+
+typedef struct {
+	gpio_num_t clk;
+	gpio_num_t mosi;
+	gpio_num_t sda; // data for I²C
+	gpio_num_t scl; // clock for I²C
+	gpio_num_t cs;
+	gpio_num_t reset;
+	gpio_num_t dc;
+} u8g2_esp32_hal_t ;
+
+#define U8G2_ESP32_HAL_DEFAULT {U8G2_ESP32_HAL_UNDEFINED, U8G2_ESP32_HAL_UNDEFINED, U8G2_ESP32_HAL_UNDEFINED, U8G2_ESP32_HAL_UNDEFINED, U8G2_ESP32_HAL_UNDEFINED, U8G2_ESP32_HAL_UNDEFINED, U8G2_ESP32_HAL_UNDEFINED }
+
+void u8g2_esp32_hal_init(u8g2_esp32_hal_t u8g2_esp32_hal_param);
+uint8_t u8g2_esp32_spi_byte_cb(u8x8_t *u8x8, uint8_t msg, uint8_t arg_int, void *arg_ptr);
+uint8_t u8g2_esp32_i2c_byte_cb(u8x8_t *u8x8, uint8_t msg, uint8_t arg_int, void *arg_ptr);
+uint8_t u8g2_esp32_gpio_and_delay_cb(u8x8_t *u8x8, uint8_t msg, uint8_t arg_int, void *arg_ptr);
+#endif /* U8G2_ESP32_HAL_H_ */
+