2026/09/H753_CPP_SPI_Resistive_Touch_Screen_Controller-doxygen-docs.zip

/*

 * STM32SPIDevice.hpp

 *

 * STM32 HAL wrapper for a single SPI peripheral + chip-select pin, providing

 * read/write/transfer helpers with automatic chip-select assert/deassert

 * bracketing.

 *

 * Adapted from Adafruit_BusIO's Adafruit_SPIDevice

 * (https://github.com/adafruit/Adafruit_BusIO, MIT License, Copyright (c)

 * 2017 Adafruit Industries) as a design reference for the transaction API

 * shape -- this is an independent STM32 HAL implementation, not a direct

 * port of Adafruit's Arduino source (which depends on Arduino-only types

 * this toolchain doesn't have). Only the hardware-SPI subset is ported:

 * Adafruit_SPIDevice's software/bit-banged-SPI fallback path has no STM32

 * HAL equivalent and is intentionally not included here.

 *

 * Unlike this project's other per-project drivers (e.g. W25QFlashSPI, which

 * references its SPI handle and CS pin via CubeMX-generated externs), this

 * class takes its SPI_HandleTypeDef and CS GPIO port/pin as constructor

 * parameters instead. STM32BusIO is meant to be reused as-is by future

 * Adafruit-derived tutorials on this site, each wiring up whatever

 * peripheral instance and CS pin their own CubeMX config generates.

 *

 *  Created on: Sep 15, 2026

 *      Author: johng

 */


#ifndef STM32BUSIO_STM32SPIDEVICE_HPP_

#define STM32BUSIO_STM32SPIDEVICE_HPP_


#include "main.h"

#include <cstddef>


class STM32SPIDevice {

public:

    STM32SPIDevice(SPI_HandleTypeDef *hspi, GPIO_TypeDef *csPort, uint16_t csPin, uint32_t timeoutMs = 100);


    void begin();


    bool read(uint8_t *buffer, size_t len, uint8_t sendValue = 0xFF);


    bool write(const uint8_t *buffer, size_t len, const uint8_t *prefixBuffer = nullptr, size_t prefixLen = 0);


    bool writeThenRead(const uint8_t *writeBuffer, size_t writeLen, uint8_t *readBuffer, size_t readLen, uint8_t sendValue = 0xFF);


    uint8_t transfer(uint8_t send);


    void transfer(uint8_t *buffer, size_t len);


    void beginTransaction();


    void endTransaction();


private:

    static constexpr size_t kMaxCombinedBytes = 32;


    SPI_HandleTypeDef *_hspi;

    GPIO_TypeDef *_csPort;

    uint16_t _csPin;

    uint32_t _timeoutMs;

};


#endif /* STM32BUSIO_STM32SPIDEVICE_HPP_ */

STM32SPIDevice
Wraps one SPI peripheral + chip-select pin into read/write/transfer operations, mirroring the hardwar...
Definition STM32SPIDevice.hpp:56

STM32SPIDevice::write
bool write(const uint8_t *buffer, size_t len, const uint8_t *prefixBuffer=nullptr, size_t prefixLen=0)
Writes len bytes from buffer, optionally preceded by a separate prefix buffer (e.g....
Definition STM32SPIDevice.cpp:51

STM32SPIDevice::begin
void begin()
Deasserts chip-select (idle-high) so the bus starts in a known state. Call once before the first tran...
Definition STM32SPIDevice.cpp:15

STM32SPIDevice::read
bool read(uint8_t *buffer, size_t len, uint8_t sendValue=0xFF)
Reads len bytes into buffer, clocking out sendValue for each byte read. Brackets the transfer with ch...
Definition STM32SPIDevice.cpp:41

STM32SPIDevice::endTransaction
void endTransaction()
Deasserts chip-select (drives it high).
Definition STM32SPIDevice.cpp:23

STM32SPIDevice::writeThenRead
bool writeThenRead(const uint8_t *writeBuffer, size_t writeLen, uint8_t *readBuffer, size_t readLen, uint8_t sendValue=0xFF)
Writes writeLen bytes, then reads readLen bytes, all within a single chip-select assert/deassert brac...
Definition STM32SPIDevice.cpp:66

STM32SPIDevice::beginTransaction
void beginTransaction()
Asserts chip-select (drives it low). No SPI settings to apply.
Definition STM32SPIDevice.cpp:19

STM32SPIDevice::STM32SPIDevice
STM32SPIDevice(SPI_HandleTypeDef *hspi, GPIO_TypeDef *csPort, uint16_t csPin, uint32_t timeoutMs=100)
Constructs the device wrapper. Does not touch hardware – HAL_GPIO_Init()/HAL_SPI_Init() for the under...
Definition STM32SPIDevice.cpp:11

STM32SPIDevice::transfer
uint8_t transfer(uint8_t send)
Transfers (sends and receives simultaneously) one byte, without chip-select management – the caller m...
Definition STM32SPIDevice.cpp:27

main.h
: Header for main.c file. This file contains the common defines of the application.