Library for M25P80 - 1MB Flash Memory IC.

This library is based on this API, but has a different implementation.

Usage

You'll need to supply:

1. Your own SPI function (spi_transceive()). I've used software version, ping me if you're interested, (it's pretty ugly);

2. Your own delay function (delay_ms());

3. Optional: Your function for DEBUG_SEND macro. I've used both SEGGER RTT and hardware UART (STM's) before.

P.S.: Tests in main.c are provided mostly as API reference and haven't been run on actual hardware, but the library itself does work.

Internals

Let's look at M25P80 memory structure. Its 1MB are made up of 4096 pages, 256 bytes each.

There are several things to look out for:

• Bits can go 0 -> 1 individually, but 1 -> 0 only sector-wise

┌─Sector 01─────────────┐
│ ┌────┐┌────┐   ┌────┐ │
│ │Page││Page│...│Page│ │
│ │0001││0002│   │0256│ │
│ └────┘└────┘   └────┘ │
├─Sector 02─────────────┤
│ ┌────┐┌────┐   ┌────┐ │
│ │Page││Page│...│Page│ │
│ │0257││0258│   │0512│ │
│ └────┘└────┘   └────┘ │
└───────────────────────┘
            :
┌─Sector 16─────────────┐
│ ┌────┐┌────┐   ┌────┐ │
│ │Page││Page│...│Page│ │
│ │3840││3841│   │4096│ │
│ └────┘└────┘   └────┘ │
└───────────────────────┘