W25Qxx Universal Driver v2.0

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The code moved to self-hosted and public git repositories due to number of issues with GitHub and Microsoft (mirrors: (m1) (m2)).

Modern rewrite of popular library.
Complete example implementations available for STM32F401 (BlackPill) and Orange PI Zero platforms.
Heavily optimized code size, improved execution speed, minimized chip access instruction sequences and RAM usage.

Feature summary

• Supported full spectrum of chip functionality (fast-read, SFDP, memory block locking, etc.)
• Production-ready code with advanced error detection and handling
• RTOS-aware implementation
  • Functions are reentrant and thread-safe
  • Embedded usage of user-defined optimized delay functions
  • Allowed mutexes to manage concurrent memory access*
• Implemented usage of some architecture-specific instructions for best performance (like 'rev' aka 'bswap32()' for ARM)
• Implemented selection of dynamic / static overwrite buffer (selected at compile time)
• Simple interfacing for any platform (see examples)
• No external dependencies
• Smart overwriting function: skips erase-write cycle for blocks containing the same data
• Built-in verification of written data for detecting bad blocks

Usage example

#include "w25qxx.h"

extern w25qxx_dev_t spi_flash_chip1; // allocated and filled with platform-specific calls and chip-specific bindings  elsewhere

int w25qxx_test(void) {
    int ret;
    char buf[W25QXX_UID_LEN] = {0}; // W25QXX_UID_LEN == 8
    
    ret = w25qxx_init(&spi_flash_chip1);
    if (ret != W25QXX_RET_SUCCESS) { // W25QXX_RET_SUCCESS == 0 
        printf("w25qxx_init(): Failed with code: %02X\r\n", ret); 
        return ret; 
    };

    ret = w25qxx_get_unique_id(&spi_flash_chip1, buf);
    if (ret) { printf("w25qxx_get_unique_id(): Failed with code: %02X (desc: '%s')\r\n", ret, w25qxx_ret2str(ret)); return ret; };

    char uid_str[W25QXX_UID_LEN * 2 + 1] = {0};
    ret = bytes2str(uid_str, buf, W25QXX_UID_LEN);
    if (ret != W25QXX_UID_LEN) { printf("bytes2str(): Failed somehow!\r\n"); return 1; };
    printf("Chip 1 UID: '%s'\r\n", uid_str);

    const int val = 123;
    const unsigned int val_addr = 0x00000000;
    
    ret = w25qxx_overwrite_verify(&spi_flash_chip1, val_addr, &val, sizeof(val));
    if (ret) { printf("w25qxx_overwrite_verify(): Failed with code: %02X (desc: '%s')\r\n", ret, w25qxx_ret2str(ret));  return ret; };

    ret = w25qxx_read_fast(&spi_flash_chip1, val_addr, buf, sizeof(ret));
    if (ret) { printf("w25qxx_read_fast(): Failed with code: %02X (desc: '%s')\r\n", ret, w25qxx_ret2str(ret));  return ret; };

    ret = *(int *)buf;
    printf("Chip 1 read data: %d\r\n", ret);

    return 0;
};