Cypress Firmware Updater

cypress-dfu is a BLE connection agnostic library for performing firmware updates to Cypress radios running the Cypress OTA DFU Bootloader.

In order to use cypress-dfu a connection needs to be established using another library such as noble (see the example for such a use case).

This library is a javascript port of the code found in the official Cypress CySmart Mobile App.

Requirements

An established connection to the Cypress radio to be updated.
A handle for sending data to the DFU characteristic
A way to pass data received from the Cypress DFU characteristic into cypress-dfu
node v6.14.2 or later for the noble example.

Installing

npm install modrobotics/node-cypress-dfu

Using

var CypressDFU = require('cypress-dfu')

//Attach listeners
CypressDFU.on('progress', function (progress) {
  console.log(['Flashing... ', progress, '%'].join(''))
})
CypressDFU.on('flashStart', function () {
  console.log('Flashing...')
})
CypressDFU.on('flashFinished', function () {
  console.log('Flashing...Success')
})
CypressDFU.on('error', function (err, code, message) {
  console.log(err, code, message)
})

//Pipe data received from your connection into the updater
yourConnection.on('data', function (data) {
  CypressDFU.onData(data)
})

//Pass in the payload(.cyacd file contents) and method that can be used to send data OTA. Begin the DFU process.
CypressDFU.startUpdate(payload, yourMethodToSendData)

Methods

startUpdate(payload, writeMethod)

Begins the DFU process.

payload (String)
- Contents of the .cyacd bootloadable file that should be flashed
writeMethod (Method)
- A method, or helper used to send data to the DFU Characteristic
- Needs to match interface: function writeMethod(data, callback)
  - data (Array) bytes to be sent to the Cypress radio
  - callback (Method) callback for when write has completed

onData(data)

Used to pipe data received over the BLE connection to the updater.

data (Array) bytes received over the BLE link.

Events

Events emitted by cypress-dfu. Event handlers can be attached by:

var CypressDFU = require('cypress-dfu')
CypressDFU.on([event_name], [params...])

flashStart

Emitted once the DFU process has begun.

CypressDFU.on('flashStart', function(){
  //
})

flashFinished

Emitted once the DFU process has completed successfully.

CypressDFU.on('flashFinished', function(){
  //
})

error

Emitted for any errors that occur during DFU. An error indicates the DFU process has failed.

CypressDFU.on('error', function(error, message, code){
  //
})

progress

Progress events while DFU is occurring. Where progress is a percentage 0-100.

CypressDFU.on('progress', function(progress){
  //
})

Flashing Flow

Flow captured from debugging the CySmart app.

Check Sum type comes from CYACD HEADER. Either Summation or CRC16

PACKET STRUCTURE
START COMMAND LEN1 LEN2 C7 FF END
  START : 1
  COMMAND: 0xZZ
  LEN1 (LSB):
  LEN2 (MSB):
  DATA: dataLength number of bytes
  CSUM1 (LSB) crc16:
  CSUM2 (MSB) crc16:
  END: 17

RESPONSE
  START STATUS DATA END

OTAEnterBootLoaderCmd
 Write request sent with value , [ 01 38 00 00 C7 FF 17  ]

 Response
 01 00 08 00 9E 11 50 0E 00 3C 01 01 AC FE 17

 OTAGetFlashSizeCmd
 Write request sent with value , [ 01 32 01 00 01 CB FF 17  ]

 Response
 01 00 04 00 D5 00 FF 01 26 FE 17

Loop:
   OTAProgramRowCmd send size--->138
   Write request sent with value , [ 01 39 83 00 01 D5 00 00 40 00 20 91 6A 01 00 F1 CB 01 00 F1 CB 01 00 80 B5 00 AF 02 4B 83 F3 08 88 06 F0 DB F8 C0 46 00 40 00 20 80 B5 00 AF 37 4B 12 22 1A 60 07 F0 3F FD 36 4B 18 00 07 F0 77 FF 01 20 07 F0 48 FD 30 20 07 F0 53 FB 32 4B 32 4A 1A 60 32 4B 80 22 D2 05 1A 60 31 4B 31 4A 12 68 02 21 0A 43 1A 60 2F 4B 30 4A 1A 60 30 4B 00 22 1A 60 2F 4B 2F 4A 12 68 08 21 8A 43 1A 60 FA 23 DB 00 18 00 07 F0 4B D5 17  ]

   OTAVerifyRowCmd
   Write request sent with value , [ 01 3A 03 00 01 D5 00 EC FE 17  ]

OTAVerifyCheckSumCmd
Write request sent with value , [ 01 31 00 00 CE FF 17  ]

OTAExitBootloaderCmd
 Write request sent with value , [ 01 3B 00 00 C4 FF 17  ]

Reponse Byte Exit>>00
Fragment Exit bootloader response>>00

modrobotics / node-cypress-dfu