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国产ARM灵动MM32使用硬件I2C总线驱动OLED显示屏源码，希望对大家有所帮助，因为STM32太贵了！建议大家拥抱国产MCU吧！

一、硬件资源

（1）主控：灵动微 MM32F103CxT6；

（2）屏幕： [灵动MM32 + I2C驱动 OLED]；

二、代码设计

1、I2C 初始化

/** * @brief Configures I2C Device port. * @param ulSpeed I2C baudrate. * @retval None */ static void Config_I2cDevice ( uint32_t ulSpeed ) { GPIO_InitTypeDef xGPIO_InitStruct; I2C_InitTypeDef xI2C_InitStruct; /* Enable clock. */ RCC_APB2PeriphClockCmd( RCC_APB2Periph_GPIOB, ENABLE ); RCC_APB1PeriphClockCmd( RCC_APB1Periph_I2C1, ENABLE ); /* Configure scl & sda GPIO parameters. */ xGPIO_InitStruct.GPIO_Mode = GPIO_Mode_AF_OD; xGPIO_InitStruct.GPIO_Pin = GPIO_Pin_6 | GPIO_Pin_7; xGPIO_InitStruct.GPIO_Speed = GPIO_Speed_10MHz; GPIO_Init( GPIOB, &xGPIO_InitStruct ); /* Configure I2C parameters. */ xI2C_InitStruct.I2C_ClockSpeed = ulSpeed; xI2C_InitStruct.I2C_Mode = I2C_Mode_MASTER; xI2C_InitStruct.I2C_OwnAddress = 0x0; if ( ulSpeed <= 100000 ) { /* Configure speed in standard mode */ xI2C_InitStruct.I2C_Speed = I2C_Speed_STANDARD; } else { /* Configure speed in fast mode */ xI2C_InitStruct.I2C_Speed = I2C_Speed_FAST; } I2C_Init( I2C1, &xI2C_InitStruct ); /* Enable i2c1 port. */ I2C_Cmd( I2C1, ENABLE ); }

2、I2C 硬件驱动

（a）、 根据官方提供源码修改，并且将其封装在 HAL_i2c 库文件内；

（b）、 该OLED 仅需要 写操作;

（c）、 在发送 STOP 停止信号前需延时 5us 才能正常显示（后续再找原因）。

/** * @brief Writes buffer of data to the I2C EEPROM. * @param pxIO ：typedef struct { GPIO_TypeDef* xPort; uint16_t usScl; uint16_t usSda; }I2C_GPIO_t; * @param pBuffer : pointer to the buffer containing the data to be written * to the EEPROM. * @param WriteAddr : EEPROM's internal address to write to. * @param NumByteToWrite : number of bytes to write to the EEPROM. * @retval None */ ErrorStatus I2C_WriteBuffer( const I2C_GPIO_t* pxIO, I2C_TypeDef* I2Cx, uint8_t DeviceAddr, uint8_t WriteAddr, uint16_t NumByteToWrite, uint8_t* pBuffer) { uint32_t I2C_Timeout; uint16_t write_Num; GPIO_InitTypeDef xGPIO_InitStruct; xGPIO_InitStruct.GPIO_Pin = pxIO->usScl | pxIO->usSda; xGPIO_InitStruct.GPIO_Speed = GPIO_Speed_10MHz; xGPIO_InitStruct.GPIO_Mode = GPIO_Mode_IPU; GPIO_Init( pxIO->xPort, &xGPIO_InitStruct ); I2C_Cmd(I2Cx, DISABLE); I2C_Send7bitAddress( I2Cx, DeviceAddr, I2C_Direction_Transmitter ); I2C_Cmd(I2Cx, ENABLE); xGPIO_InitStruct.GPIO_Mode = GPIO_Mode_AF_OD; GPIO_Init( pxIO->xPort, &xGPIO_InitStruct ); I2C_SendData( I2Cx, WriteAddr ); I2C_Timeout = 0x1000; while ( ( I2C_GetFlagStatus( I2Cx, I2C_STATUS_FLAG_TFE ) ) == RESET ) { if ( ( I2C_Timeout-- ) == 0 ) { return ERROR; } } for ( write_Num=0; write_Num0; i-- ); I2C_GenerateSTOP( I2Cx, ENABLE ); I2C_Timeout = 0x1000; while ( ( I2C_GetITStatus( I2Cx, I2C_IT_STOP_DET ) ) == RESET ) { if ( ( I2C_Timeout-- ) == 0 ) { return ERROR; } } /* If all operations OK, return sEE_OK (0) */ return SUCCESS; }

3、OLED 程序模块

仅提供 Cmd & Data 部分，大部分和网络上的大同小异，可参考（正点原子、中景园电子、etc）。这篇文章主要是 MM32 的 I2C。

/** * @brief Write commands to the screen. * @param ucCmd Write command to be written. * @retval None. */ static void Screen_WriteCmd( uint8_t ucCmd ) { I2C_WriteBuffer( &xConfig, I2C_DEVICE, I2C_ADDR, 0x00, 1, &ucCmd ); } /** * @brief Write data to the screen. * @param ucCmd Write data to be written. * @retval None. */ static void Screen_WriteDat( uint8_t ucDat ) { I2C_WriteBuffer( &xConfig, I2C_DEVICE, I2C_ADDR, 0x40, 1, &ucDat ); }