前言
在本文中，我们将介绍如何在STM32上成功地移植u8g2图形库，以便能够轻松地控制OLED或LCD显示屏。u8g2库提供了一个灵活、功能强大的框架，可以简化图形界面的开发过程。通过合理地配置STM32 CubeMX以及适当的硬件连接，我们可以使得u8g2与STM32微控制器完美结合。
我们将逐步引导您完成整个移植过程，从STM32 CubeMX的项目创建，到u8g2库的集成和配置，最终实现一个简单的示例程序，以确保整个过程的顺利进行。让我们一起开始吧！
一、下载u8g2源文件
如果进不去可以私信我。找我要源代码。
下载好之后解压出来
二、复制和更改文件
2.1 复制文件
1、首先，在工程下面创建一个u8g2文件夹
2、把我们下载好的u8g2文件夹里面的csrc下图中的这些文件复制进去
3、在工程中创建一个drive文件夹，里面放oled文件夹，oled文件夹放oled.c和oled.h，之后有用
4、打开keil，把前面的这些文件放进去
2.2 修改文件
u8g2_d_setup文件
我们需要找到下面这个函数：
void u8g2_Setup_ssd1306_i2c_128x64_noname_f(u8g2_t *u8g2, const u8g2_cb_t *rotation, u8x8_msg_cb byte_cb, u8x8_msg_cb gpio_and_delay_cb) { uint8_t tile_buf_height; uint8_t *buf; u8g2_SetupDisplay(u8g2, u8x8_d_ssd1306_128x64_noname, u8x8_cad_ssd13xx_fast_i2c, byte_cb, gpio_and_delay_cb); buf = u8g2_m_16_8_f(&tile_buf_height); u8g2_SetupBuffer(u8g2, buf, tile_buf_height, u8g2_ll_hvline_vertical_top_lsb, rotation); }
然后把其他函数给删除或者注释掉。
u8g2_d_memory
我们需要找到下面这个函数
uint8_t *u8g2_m_16_8_f(uint8_t *page_cnt) { #ifdef U8G2_USE_DYNAMIC_ALLOC *page_cnt = 8; return 0; #else static uint8_t buf[1024]; *page_cnt = 8; return buf; #endif }
把其他函数删除或注释掉.
三、编写oled.c和oled.h文件
3.1 CubeMX配置I2C
首先我们在CubeMX配置好我们的I2C，这个在之前的文章已经讲过了，这里不多赘述。
3.2 编写文件
oled.h
我们在oled.h文件里面，把下面的代码复制进去就可以了
#ifndef __oled_H #define __oled_H #ifdef __cplusplus extern "C" { #endif /* Includes ------------------------------------------------------------------*/ #include "main.h" #include "u8g2.h" /* USER CODE BEGIN Includes */ /* USER CODE END Includes */ /* USER CODE BEGIN Private defines */ /* USER CODE END Private defines */ #define u8 unsigned char // ?unsigned char ???? #define MAX_LEN 128 // #define OLED_ADDRESS 0x78 // oled?????? #define OLED_CMD 0x00 // ??? #define OLED_DATA 0x40 // ??? /* USER CODE BEGIN Prototypes */ uint8_t u8x8_byte_hw_i2c(u8x8_t *u8x8, uint8_t msg, uint8_t arg_int, void *arg_ptr); uint8_t u8x8_gpio_and_delay(u8x8_t *u8x8, uint8_t msg, uint8_t arg_int, void *arg_ptr); void u8g2Init(u8g2_t *u8g2); #ifdef __cplusplus } #endif #endif /*__ i2c_H */ /* USER CODE END Prototypes */
oled.c
我们需要把MX_I2C1_Init，这个函数复制进去，这个函数是CubeMX生成的不需要我们自己写，如果你的函数名和我的不同，那就把u8x8_byte_hw_i2c里面的MX_I2C1_Init替换成你的函数
#include "stm32f1xx_hal.h" #include "u8g2.h" #include "oled.h" #include "delay.h" #include "main.h" #include "oled.h" I2C_HandleTypeDef hi2c1; static void MX_I2C1_Init(void) { /* USER CODE BEGIN I2C1_Init 0 */ /* USER CODE END I2C1_Init 0 */ /* USER CODE BEGIN I2C1_Init 1 */ /* USER CODE END I2C1_Init 1 */ hi2c1.Instance = I2C1; hi2c1.Init.ClockSpeed = 400000; hi2c1.Init.DutyCycle = I2C_DUTYCYCLE_2; hi2c1.Init.OwnAddress1 = 0; hi2c1.Init.AddressingMode = I2C_ADDRESSINGMODE_7BIT; hi2c1.Init.DualAddressMode = I2C_DUALADDRESS_DISABLE; hi2c1.Init.OwnAddress2 = 0; hi2c1.Init.GeneralCallMode = I2C_GENERALCALL_DISABLE; hi2c1.Init.NoStretchMode = I2C_NOSTRETCH_DISABLE; if (HAL_I2C_Init(&hi2c1) != HAL_OK) { Error_Handler(); } /* USER CODE BEGIN I2C1_Init 2 */ /* USER CODE END I2C1_Init 2 */ } uint8_t u8x8_byte_hw_i2c(u8x8_t *u8x8, uint8_t msg, uint8_t arg_int, void *arg_ptr) { /* u8g2/u8x8 will never send more than 32 bytes between START_TRANSFER and END_TRANSFER */ static uint8_t buffer[128]; static uint8_t buf_idx; uint8_t *data; switch (msg) { case U8X8_MSG_BYTE_INIT: { /* add your custom code to init i2c subsystem */ MX_I2C1_Init(); //I2C??? } break; case U8X8_MSG_BYTE_START_TRANSFER: { buf_idx = 0; } break; case U8X8_MSG_BYTE_SEND: { data = (uint8_t *)arg_ptr; while (arg_int > 0) { buffer[buf_idx++] = *data; data++; arg_int--; } } break; case U8X8_MSG_BYTE_END_TRANSFER: { if (HAL_I2C_Master_Transmit(&hi2c1, (OLED_ADDRESS), buffer, buf_idx, 1000) != HAL_OK) return 0; } break; case U8X8_MSG_BYTE_SET_DC: break; default: return 0; } return 1; } void delay_us(uint32_t time) { uint32_t i = 8 * time; while (i--) ; } uint8_t u8x8_gpio_and_delay(u8x8_t *u8x8, uint8_t msg, uint8_t arg_int, void *arg_ptr) { switch (msg) { case U8X8_MSG_DELAY_100NANO: // delay arg_int * 100 nano seconds __NOP(); break; case U8X8_MSG_DELAY_10MICRO: // delay arg_int * 10 micro seconds for (uint16_t n = 0; n < 320; n++) { __NOP(); } break; case U8X8_MSG_DELAY_MILLI: // delay arg_int * 1 milli second HAL_Delay(1); break; case U8X8_MSG_DELAY_I2C: // arg_int is the I2C speed in 100KHz, e.g. 4 = 400 KHz delay_us(5); break; // arg_int=1: delay by 5us, arg_int = 4: delay by 1.25us case U8X8_MSG_GPIO_I2C_CLOCK: // arg_int=0: Output low at I2C clock pin break; // arg_int=1: Input dir with pullup high for I2C clock pin case U8X8_MSG_GPIO_I2C_DATA: // arg_int=0: Output low at I2C data pin break; // arg_int=1: Input dir with pullup high for I2C data pin case U8X8_MSG_GPIO_MENU_SELECT: u8x8_SetGPIOResult(u8x8, /* get menu select pin state */ 0); break; case U8X8_MSG_GPIO_MENU_NEXT: u8x8_SetGPIOResult(u8x8, /* get menu next pin state */ 0); break; case U8X8_MSG_GPIO_MENU_PREV: u8x8_SetGPIOResult(u8x8, /* get menu prev pin state */ 0); break; case U8X8_MSG_GPIO_MENU_HOME: u8x8_SetGPIOResult(u8x8, /* get menu home pin state */ 0); break; default: u8x8_SetGPIOResult(u8x8, 1); // default return value break; } return 1; } void u8g2Init(u8g2_t *u8g2) { u8g2_Setup_ssd1306_i2c_128x64_noname_f(u8g2, U8G2_R0, u8x8_byte_hw_i2c, u8x8_gpio_and_delay); // ??? u8g2 ??? u8g2_InitDisplay(u8g2); // ??????????????,??????,????????? u8g2_SetPowerSave(u8g2, 0); // ????? u8g2_ClearBuffer(u8g2); }
四、测试代码
到这里已经大功告成了，最后我们需要设置一下为C99标准：
main函数测试代码
/* USER CODE BEGIN Header */ /** ****************************************************************************** * @file : main.c * @brief : Main program body ****************************************************************************** * @attention * * Copyright (c) 2023 STMicroelectronics. * All rights reserved. * * This software is licensed under terms that can be found in the LICENSE file * in the root directory of this software component. * If no LICENSE file comes with this software, it is provided AS-IS. * ****************************************************************************** */ /* USER CODE END Header */ /* Includes ------------------------------------------------------------------*/ #include "main.h" /* Private includes ----------------------------------------------------------*/ /* USER CODE BEGIN Includes */ #include "u8g2.h" #include "oled.h" /* USER CODE END Includes */ /* Private typedef -----------------------------------------------------------*/ /* USER CODE BEGIN PTD */ /* USER CODE END PTD */ /* Private define ------------------------------------------------------------*/ /* USER CODE BEGIN PD */ /* USER CODE END PD */ /* Private macro -------------------------------------------------------------*/ /* USER CODE BEGIN PM */ /* USER CODE END PM */ /* Private variables ---------------------------------------------------------*/ /* USER CODE BEGIN PV */ /* USER CODE END PV */ /* Private function prototypes -----------------------------------------------*/ void SystemClock_Config(void); static void MX_GPIO_Init(void); static void MX_I2C1_Init(void); /* USER CODE BEGIN PFP */ /* USER CODE END PFP */ /* Private user code ---------------------------------------------------------*/ /* USER CODE BEGIN 0 */ /* USER CODE END 0 */ /** * @brief The application entry point. * @retval int */ int main(void) { /* USER CODE BEGIN 1 */ /* USER CODE END 1 */ /* MCU Configuration--------------------------------------------------------*/ /* Reset of all peripherals, Initializes the Flash interface and the Systick. */ HAL_Init(); /* USER CODE BEGIN Init */ /* USER CODE END Init */ /* Configure the system clock */ SystemClock_Config(); /* USER CODE BEGIN SysInit */ /* USER CODE END SysInit */ /* Initialize all configured peripherals */ MX_GPIO_Init(); /* USER CODE BEGIN 2 */ /* USER CODE END 2 */ /* Infinite loop */ /* USER CODE BEGIN WHILE */ u8g2_t u8g2; // a structure which will contain all the data for one display u8g2Init(&u8g2); /* USER CODE END 2 */ /* Infinite loop */ /* USER CODE BEGIN WHILE */ while (1) { /* USER CODE END WHILE */ //u8g2_DrawCircle(&u8g2, 64, 32, 30, U8G2_DRAW_ALL); u8g2_SendBuffer(&u8g2); u8g2_DrawBox(&u8g2,0,0,20,20); u8g2_DrawBox(&u8g2,20,20,20,20); u8g2_SendBuffer(&u8g2); u8g2_DrawFrame(&u8g2,10,40,20,20); u8g2_SendBuffer(&u8g2); u8g2_SetFont(&u8g2,u8g2_font_DigitalDiscoThin_tf); u8g2_DrawStr(&u8g2,30,10,"Hello World"); u8g2_SendBuffer(&u8g2); HAL_Delay(1000); /* USER CODE BEGIN 3 */ } /* USER CODE END 3 */ } /** * @brief System Clock Configuration * @retval None */ void SystemClock_Config(void) { RCC_OscInitTypeDef RCC_OscInitStruct = {0}; RCC_ClkInitTypeDef RCC_ClkInitStruct = {0}; /** Initializes the RCC Oscillators according to the specified parameters * in the RCC_OscInitTypeDef structure. */ RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSE; RCC_OscInitStruct.HSEState = RCC_HSE_ON; RCC_OscInitStruct.HSEPredivValue = RCC_HSE_PREDIV_DIV1; RCC_OscInitStruct.HSIState = RCC_HSI_ON; RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON; RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSE; RCC_OscInitStruct.PLL.PLLMUL = RCC_PLL_MUL9; if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK) { Error_Handler(); } /** Initializes the CPU, AHB and APB buses clocks */ RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK|RCC_CLOCKTYPE_SYSCLK |RCC_CLOCKTYPE_PCLK1|RCC_CLOCKTYPE_PCLK2; RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK; RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1; RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV2; RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1; if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_2) != HAL_OK) { Error_Handler(); } } /** * @brief I2C1 Initialization Function * @param None * @retval None */ /** * @brief GPIO Initialization Function * @param None * @retval None */ static void MX_GPIO_Init(void) { /* GPIO Ports Clock Enable */ __HAL_RCC_GPIOA_CLK_ENABLE(); __HAL_RCC_GPIOB_CLK_ENABLE(); } /* USER CODE BEGIN 4 */ /* USER CODE END 4 */ /** * @brief This function is executed in case of error occurrence. * @retval None */ void Error_Handler(void) { /* USER CODE BEGIN Error_Handler_Debug */ /* User can add his own implementation to report the HAL error return state */ __disable_irq(); while (1) { } /* USER CODE END Error_Handler_Debug */ } #ifdef USE_FULL_ASSERT /** * @brief Reports the name of the source file and the source line number * where the assert_param error has occurred. * @param file: pointer to the source file name * @param line: assert_param error line source number * @retval None */ void assert_failed(uint8_t *file, uint32_t line) { /* USER CODE BEGIN 6 */ /* User can add his own implementation to report the file name and line number, ex: printf("Wrong parameters value: file %s on line %d\r\n", file, line) */ /* USER CODE END 6 */ } #endif /* USE_FULL_ASSERT */
我们编译，烧写，即可看到oled已经显示了！
总结
通过本文的介绍与实践，我们成功地将u8g2图形库移植到了STM32微控制器上，并实现了一个简单的示例程序。以下是我们在整个过程中所取得的关键成果：
STM32 CubeMX项目创建：我们从零开始使用了STM32 CubeMX创建了一个新的项目，确保了正确的初始化和配置。
硬件连接：通过正确地连接OLED或LCD显示屏到STM32微控制器，我们保证了u8g2能够与硬件正确通信。
u8g2库的集成与配置：我们成功地将u8g2库添加到了STM32 CubeMX项目中，并配置了相关的参数，以确保适应我们的硬件需求。
示例程序的编写：我们编写了一个简单的示例程序，以验证u8g2库的正确移植与配置。
通过这个实例，我们展示了如何在STM32上成功地移植u8g2库，为您在嵌入式图形界面开发中提供了一个强大的工具。希望本文对您在此方面的工作和项目中能够提供有价值的参考。祝您的项目取得圆满成功！
