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USART MCAL Module

Supported STM32 families: F4 · G4 · H5 · U5
Not supported: H7, L4

This module provides an abstraction layer for configuring and managing USART peripherals on STM32 MCUs.
It supports initialization, configuration of communication parameters, DMA transfers, interrupt handling, and GPIO setup.

Features​

  • Basic initialization and deinitialization
  • Configuration of baudrate, data width, stop bits, parity, transfer mode, flow control
  • Driver enable feature and polarity
  • Oversampling and half-duplex support
  • RX timeout configuration
  • Pin levels management
  • Direct register access for TX/RX
  • Blocking and non-blocking transfers
  • DMA-based data transfers (TX/RX)
  • Full interrupt handling support with callbacks
  • GPIO pin initialization for USART signals

Public API​

Module Management​

  • usart_ModuleVersion_t Usart_Get_ModuleVersion(void);
  • usart_RequestState_t Usart_Init(usart_BusConfig_t * const usartConfig);
  • usart_RequestState_t Usart_Deinit(usart_PeriphId_t usartId);
  • void Usart_Task(void);
  • usart_RequestState_t Usart_Get_DefaultConfig(usart_BusConfig_t *usartConfig);

Peripheral Control​

  • usart_RequestState_t Usart_Set_PeriphActive(usart_PeriphId_t usartId);
  • usart_RequestState_t Usart_Set_PeriphInactive(usart_PeriphId_t usartId);
  • usart_RequestState_t Usart_Get_PeriphState(usart_PeriphId_t usartId, usart_FlagState_t * const reqState);

Communication Settings​

  • usart_RequestState_t Usart_Set_Baudrate(usart_PeriphId_t usartId, usart_Baudrate_t baudrate);
  • usart_RequestState_t Usart_Get_Baudrate(usart_PeriphId_t usartId, usart_Baudrate_t * const baudrate);
  • usart_RequestState_t Usart_Set_DataWidth(usart_PeriphId_t usartId, usart_DataWidth_t dataWidth);
  • usart_RequestState_t Usart_Get_DataWidth(usart_PeriphId_t usartId, usart_DataWidth_t * const dataWidth);
  • usart_RequestState_t Usart_Set_StopBits(usart_PeriphId_t usartId, usart_StopBits_t stopBits);
  • usart_RequestState_t Usart_Get_StopBits(usart_PeriphId_t usartId, usart_StopBits_t * const stopBits);
  • usart_RequestState_t Usart_Set_Parity(usart_PeriphId_t usartId, usart_Parity_t parity);
  • usart_RequestState_t Usart_Get_Parity(usart_PeriphId_t usartId, usart_Parity_t * const parity);
  • usart_RequestState_t Usart_Set_TransferMode(usart_PeriphId_t usartId, usart_TransferMode_t transferMode);
  • usart_RequestState_t Usart_Get_TransferMode(usart_PeriphId_t usartId, usart_TransferMode_t * const transferMode);
  • usart_RequestState_t Usart_Set_FlowControl(usart_PeriphId_t usartId, usart_FlowControl_t flowControl);
  • usart_RequestState_t Usart_Get_FlowControl(usart_PeriphId_t usartId, usart_FlowControl_t * const flowControl);

Driver Enable and Timing​

  • usart_RequestState_t Usart_Set_DriverEnableState(usart_PeriphId_t usartId, usart_DeFeatureState_t deState);
  • usart_RequestState_t Usart_Get_DriverEnableState(usart_PeriphId_t usartId, usart_DeFeatureState_t * const deState);
  • usart_RequestState_t Usart_Set_DriverEnablePolarity(usart_PeriphId_t usartId, usart_DePolarity_t dePolarity);
  • usart_RequestState_t Usart_Get_DriverEnablePolarity(usart_PeriphId_t usartId, usart_DePolarity_t * const dePolarity);
  • usart_RequestState_t Usart_Set_AssertDeassertTimes(usart_PeriphId_t usartId, usart_AssertTime_us_t assertTime, usart_DeassertTime_us_t deassertTime);
  • usart_RequestState_t Usart_Get_AssertDeassertTimes(usart_PeriphId_t usartId, usart_AssertTime_us_t * const assertTime, usart_DeassertTime_us_t * const deassertTime);

Advanced Communication Settings​

  • usart_RequestState_t Usart_Set_Oversampling(usart_PeriphId_t usartId, usart_Oversampling_t oversamplingMode);
  • usart_RequestState_t Usart_Get_Oversampling(usart_PeriphId_t usartId, usart_Oversampling_t * const oversamplingMode);
  • usart_RequestState_t Usart_Set_HalfDuplexState(usart_PeriphId_t usartId, usart_HalfDuplex_t halfDuplexState);
  • usart_RequestState_t Usart_Get_HalfDuplexState(usart_PeriphId_t usartId, usart_HalfDuplex_t * const halfDuplexState);
  • usart_RequestState_t Usart_Set_RxTimeoutActive(usart_PeriphId_t usartId, usart_RxTimeout_t timeoutBitsCnt);
  • usart_RequestState_t Usart_Set_RxTimeoutInactive(usart_PeriphId_t usartId);
  • usart_RequestState_t Usart_Get_RxTimeoutState(usart_PeriphId_t usartId, usart_FlagState_t * const reqState);

Pin Management​

  • usart_RequestState_t Usart_Set_PinLevels(usart_PeriphId_t usartId, usart_RxPinLevel_t rxPinLevels, usart_TxPinLevel_t txPinLevels);
  • usart_RequestState_t Usart_Get_PinLevels(usart_PeriphId_t usartId, usart_RxPinLevel_t * const rxPinLevels, usart_TxPinLevel_t * const txPinLevels);
  • usart_RequestState_t Usart_Get_TxRegisterAddr(usart_PeriphId_t usartId, usart_RxRegAddr_t * const regAddr);
  • usart_RequestState_t Usart_Get_RxRegisterAddr(usart_PeriphId_t usartId, usart_RxRegAddr_t * const regAddr);

Data Transfer​

  • void Usart_SendData(usart_PeriphId_t usartId, usart_TxData_t txData);
  • usart_RxData_t Usart_ReadData(usart_PeriphId_t usartId);

DMA Support​

  • usart_RequestState_t Usart_Init_Dma(usart_PeriphId_t usartId, usart_DmaConfig_t * const dmaConfig);
  • TX:
    • usart_RequestState_t Usart_Set_DmaTxStart(usart_PeriphId_t usartId, usart_TxDataCnt_t bytesCnt, usart_TxData_t * const dataBuff);
    • usart_RequestState_t Usart_Set_DmaTxStop(usart_PeriphId_t usartId);
    • usart_RequestState_t Usart_Get_DmaTxRemainingCnt(usart_PeriphId_t usartId, usart_TxDataCnt_t * const bytesCnt);
  • RX:
    • usart_RequestState_t Usart_Set_DmaRxStart(usart_PeriphId_t usartId, usart_RxDataCnt_t bytesCnt, usart_RxData_t * const dataBuff);
    • usart_RequestState_t Usart_Set_DmaRxStop(usart_PeriphId_t usartId);
    • usart_RequestState_t Usart_Get_DmaRxRemainingCnt(usart_PeriphId_t usartId, usart_RxDataCnt_t * const bytesCnt);
  • DMA Requests:
    • usart_RequestState_t Usart_Set_DmaTxRequestActive(usart_PeriphId_t usartId);
    • usart_RequestState_t Usart_Set_DmaTxRequestInactive(usart_PeriphId_t usartId);
    • usart_RequestState_t Usart_Get_DmaTxReqState(usart_PeriphId_t usartId, usart_FlagState_t * const reqState);
    • usart_RequestState_t Usart_Set_DmaRxRequestActive(usart_PeriphId_t usartId);
    • usart_RequestState_t Usart_Set_DmaRxRequestInactive(usart_PeriphId_t usartId);
    • usart_RequestState_t Usart_Get_DmaRxReqState(usart_PeriphId_t usartId, usart_FlagState_t * const reqState);

Interrupts and Callbacks​

  • General:
    • usart_RequestState_t Usart_Set_InterruptsActive(usart_PeriphId_t usartBus);
    • usart_RequestState_t Usart_Set_InterruptsInactive(usart_PeriphId_t usartBus);
    • usart_RequestState_t Usart_Set_IrqPriority(usart_PeriphId_t usartId, usart_IrqPrio_t irqPrio);
    • usart_RequestState_t Usart_Get_IrqPriority(usart_PeriphId_t usartId, usart_IrqPrio_t * const irqPrio);
  • RX Not Empty:
    • usart_RequestState_t Usart_Set_RxNotEmptyIrqActive(usart_PeriphId_t usartId);
    • usart_RequestState_t Usart_Set_RxNotEmptyIrqInactive(usart_PeriphId_t usartId);
    • usart_RequestState_t Usart_Get_RxNotEmptyIrqState(usart_PeriphId_t usartId, usart_FlagState_t * const reqState);
    • usart_RequestState_t Usart_Set_RxNotEmptyIsrCallback(usart_PeriphId_t usartId, usart_RxNeIrqCallback_t * const callback);
  • TX Empty:
    • usart_RequestState_t Usart_Set_TxEmptyIrqActive(usart_PeriphId_t usartId);
    • usart_RequestState_t Usart_Set_TxEmptyIrqInactive(usart_PeriphId_t usartId);
    • usart_RequestState_t Usart_Get_TxEmptyIrqState(usart_PeriphId_t usartId, usart_FlagState_t * const reqState);
    • usart_RequestState_t Usart_Set_TxEmptyIsrCallback(usart_PeriphId_t usartId, usart_TxeIrqCallback_t * const callback);
  • TX Complete:
    • usart_RequestState_t Usart_Set_TxCompleteIrqActive(usart_PeriphId_t usartId);
    • usart_RequestState_t Usart_Set_TxCompleteIrqInactive(usart_PeriphId_t usartId);
    • usart_RequestState_t Usart_Get_TxCompleteIrqState(usart_PeriphId_t usartId, usart_FlagState_t * const reqState);
    • usart_RequestState_t Usart_Set_TxCompleteIsrCallback(usart_PeriphId_t usartId, usart_TcIrqCallback_t * const callback);
  • Idle:
    • usart_RequestState_t Usart_Set_IdleIrqActive(usart_PeriphId_t usartId);
    • usart_RequestState_t Usart_Set_IdleIrqInactive(usart_PeriphId_t usartId);
    • usart_RequestState_t Usart_Get_IdleIrqState(usart_PeriphId_t usartId, usart_FlagState_t * const reqState);
    • usart_RequestState_t Usart_Set_IdleIsrCallback(usart_PeriphId_t usartId, usart_IdleIrqCallback_t * const callback);
  • RX Timeout:
    • usart_RequestState_t Usart_Set_RxTimeoutIrqActive(usart_PeriphId_t usartId);
    • usart_RequestState_t Usart_Set_RxTimeoutIrqInactive(usart_PeriphId_t usartId);
    • usart_RequestState_t Usart_Get_RxTimeoutIrqState(usart_PeriphId_t usartId, usart_FlagState_t * const reqState);
    • usart_RequestState_t Usart_Set_RxTimeoutIsrCallback(usart_PeriphId_t usartId, usart_RxTimeoutIrqCallback_t * const callback);
  • Error:
    • usart_RequestState_t Usart_Set_ErrorIrqActive(usart_PeriphId_t usartId);
    • usart_RequestState_t Usart_Set_ErrorIrqInactive(usart_PeriphId_t usartId);
    • usart_RequestState_t Usart_Get_ErrorIrqState(usart_PeriphId_t usartId, usart_FlagState_t * const reqState);
    • usart_RequestState_t Usart_Set_ErrorIsrCallback(usart_PeriphId_t usartId, usart_ErrIrqCallback_t * const callback);

GPIO Configuration​

  • usart_RequestState_t Usart_InitRxGpio(usart_RxPin_t pinId);
  • usart_RequestState_t Usart_InitTxGpio(usart_TxPin_t pinId);
  • usart_RequestState_t Usart_InitDeGpio(usart_DePin_t pinId);

🛠 CMake Integration​

  1. Include Usart_Lib in your CMake library.
  2. Include Usart_Port.h in your project.
  3. Link against the Usart module implementation files.
  4. Configure the module as needed for your hardware.

License​

This project is licensed under the Creative Commons Attribution–NonCommercial 4.0 International (CC BY-NC 4.0).

You are free to use, modify, and share this work for non-commercial purposes, provided appropriate credit is given.

See LICENSE.md for full terms or visit creativecommons.org/licenses/by-nc/4.0.

Authors​

Contributions are welcome! Please open a pull request.