RFIL

Use our NPM package here!

npm i rfil

or use yarn

yarn add rfil

Usage

You can either use commonjs or esm.

CommonJS

const { parse } = require('rfil');
const fs = require('fs');

// Read a buffer from a file
const buffer = fs.readFileSync('file.rfil');

// Parse the buffer
const data = parse(buffer);

// Print the data
console.log(data);

ESM

import { parse } from 'rfil';
import fs from 'node:fs';

// Read a buffer from a file
const buffer = fs.readFileSync('file.rfil');

// Parse the buffer
const data = parse(buffer);

// Print the data
console.log(data);

Exporting raw files

Here's an example on how to export raw files from a RFIL file.

import { parse } from 'rfil';
import fs from 'node:fs';
import path from 'node:path';

// Read a buffer from a file
const buffer = fs.readFileSync('file.rfil');

// Parse the buffer
const data = parse(buffer);

// Check for data
if (!data.hasData()) {
    console.log('An error occurred: %s', data.hasError() ? data.unwrapError() : '[Unknown error]');
    process.exit(1);
}

// Write files
data.unwrap().data.forEach((data, index) => {
    fs.writeFileSync(path.join(process.cwd(), `out${index}.raw`), data.data);
});

RFIL File Format

I will be calling the flipper zero file format RFIL because the magic bytes are 0x4C464952 which is RFIL in ASCII. This is a decoder for the RFIL file format written in TypeScript.

File Structure

There are 2 parts in a RFIL file: the header and the data. It is also encoded in this little s*** (💩) called little endian.

Header

The header first starts with a 32 bit (4 byte) magic number 0x4C464952 which is RFIL in ASCII.

Next there is a 32 bit (4 byte) integer with the version of the file format. Currently the version is 1.

Next there is a 32 bit (4 byte) float encoded in IEEE 754. This represents the frequency of the file in Hz.

Next there is another 32 bit (4 byte) float encoded in IEEE 754. This represents the duty cycle of the file in percent.

Finaly there is a 32 bit (4 byte) integer with the length of the data in bytes.

Here is a table with the header structure:

Offset	Length	Type	Description	Example
0x00	0x04	uint32	Magic number	0x4C464952
0x04	0x04	uint32	Version	0x10000000
0x08	0x04	float32	Frequency	0x0024F447 (for ASK 125kHz)
0x0C	0x04	float32	Duty cycle	0x0000003F (for 0.5 seconds)
0x10	0x04	uint32	Data length	0x0000000A (for 10 bytes)

Data

The data is just a bunch of bytes in pairs.

The first part is the length of the data in bytes. This is a 32 bit (4 byte) integer. Or size_t in C. Note: size_t is not always 32 bit. It depends on the compiler. It is at least 16 bit. So this is not portable. But I don't care.

The second part is the data itself. This is a buffer with the length of the first part.

Here is a table with the data structure:

Offset	Length	Type	Description	Example
0x00	0x01	uint32	Data length	0x0A (for 10 bytes)
0x04	0x0A	uint8[]	Data	0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00