Crate avr_boot

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Expand description

Avr Boot

This crate contains functions to write to the program memory of AVR MCUs, using the spm instruction.

It could be considered a reimagining of the macros in boot.h from avr-libc, but in Rust, plus some artisanal, hand-crafted asm. If you’re looking to create a bootloader, this crate should be useful.

It is hal independent, and optimised for code size.

Regular and extended (>64k) addressing modes are supported.

Getting started

Add the module to your Cargo.toml:

[dependencies]
avr-boot = "0.1.0"

Pick from the high level API:

use avr_boot::PageBuffer;

let address: u16 = 0x1000;
let data = [0xffff; PageBuffer::LENGTH];
let buff = PageBuffer::new(address);
buff.copy_from(&data);
buff.store();

Or the low level one:

use avr_boot::{spm, SPM_PAGESIZE_WORDS, Address};

let page_address: u16 = 0x1000;
for w in 0..SPM_PAGESIZE_WORDS {
    spm::fill_page((page_address + (w * 2) as u16), 0x1234);
}
spm::erase_page(page_address);
spm::write_page(page_address);
spm::rww_enable();

Check out the examples module for more usage examples

Modules

  • spm
    Low level API for calling bootloader functions

Structs

  • Address
    16 or 24 bit program memory address
  • DataPage
    NewType, an array of memory the same size as the page buffer
  • PageBuffer
    Representation of the spm page buffer.

Constants