netanelgonen / spif-driver

Block device driver for NOR SPI flash devices that support SFDP, such as the MX25R or SST26F016B

SPI Flash Driver

Block device driver for NOR based SPI flash devices that support SFDP.

NOR based SPI flash supports byte-sized read and writes, with an erase size of around 4kbytes. An erase sets a block to all 1s, with successive writes clearing set bits.

More info on NOR flash can be found on wikipedia: https://en.wikipedia.org/wiki/Flash_memory#NOR_memories

// Here's an example using the MX25R SPI flash device on the K82F
#include "mbed.h"
#include "SPIFBlockDevice.h"

// Create flash device on SPI bus with PTE5 as chip select
SPIFBlockDevice spif(PTE2, PTE4, PTE1, PTE5);

int main() {
    printf("spif test\n");

    // Initialize the SPI flash device and print the memory layout
    spif.init();
    printf("spif size: %llu\n",         spif.size());
    printf("spif read size: %llu\n",    spif.get_read_size());
    printf("spif program size: %llu\n", spif.get_program_size());
    printf("spif erase size: %llu\n",   spif.get_erase_size());

    // Write "Hello World!" to the first block
    char *buffer = (char*)malloc(spif.get_erase_size());
    sprintf(buffer, "Hello World!\n");
    spif.erase(0, spif.get_erase_size());
    spif.program(buffer, 0, spif.get_erase_size());

    // Read back what was stored
    spif.read(buffer, 0, spif.get_erase_size());
    printf("%s", buffer);

    // Deinitialize the device
    spif.deinit();
}