An open hardware project for digital switching on boats, or anywhere with 12v-24v systems.
The project is based around the amazing esp32 and currently consists of one board, an 8-channel mosfet driver. With this board, you can control almost any DC load on your boat. There are future plans to design a relay board, an I/O board, etc.
Pronounced yarrrrrrr * bird. Lots of r's and don't call it a board. ;)
The project is broken into a few different repositories:
The main (and only) board available is for driving DC loads. It is designed with common DC loads in mind, such as: lights, pumps, motors, relays, and other electronics. Here are some specifications:
- 12v to 30v supply voltage (supports both lead acid and lithium battery systems in either 12v or 24v configuration)
- 8 separately controllable channels with PWM capability on each channel
- Each channel capable of up to 20A, with appropriate cooling
- Current monitoring accurate to about 0.01A on each channel
- Firmware supports soft fuses to protect from overcurrent
- Made with heavy duty 2oz copper and thick copper busbars to handle big loads
- Each channel is individually fused, with a manual bypass in case of MOSFET failure
- Potential expandability with QWIIC headers and a serial port for possible NMEA2000
- 3D printable case w/ design files
Since it is based on the esp32, the main communication method is over WiFi. Setup, config, and control are very easy using the built-in web portal. Just point your phone to the url of the board and you're good to go. Typically this is http://yarrboard.local or http://yarrboard. You can change this hostname in the settings, or use the IP address instead.
There is also a plugin for integration with SignalK, so you can have your data all in one place. It supports two way comms, so you can use SignalK and Node-RED to turn your loads on or off.
The plugin for SignalK is called signalk-yarrboard-plugin
No production as of right now, but possibly in the future. It is 100% open source, so its possible to order PCBs, parts, and DIY your own board if you like. There is the potential of partnering with the right person to take care of the manufacturing side of things, or you could make and sell your own - its open source after all!
- Assemble the board
- Plug your computer into esp32 with a USB cable
- Flash the firmware (use VSCode + Platformio and open the /firmware folder in this repository)
- Upload the SPIFFS file system ("Upload Filesystem Image" in VSCode)
- Connect to Yarrboard wifi
- Open browser to http://yarrboard.local or http://yarrboard
- Update network settings to connect to your boat wifi
- Reconnect your phone to your boat wifi
- Open browser to http://yarrboard.local or http://yarrboard
- Update board settings, such as login info, channel names, soft fuses, etc.
- Install SignalK + signalk-yarrboard-plugin and configure
- Setup any Node-RED flows and custom logic you want.
The protocol for communicating with Yarrboard is entirely based on JSON. Each request to the server should be a single JSON object, and the server will respond with a JSON object.
Here are some example commands you could send:
{"cmd":"ping"}
{"cmd":"get_config","value":true,"user":"admin","pass":"admin"}
{"cmd":"set_channel","id":0,"state":true,"user":"admin","pass":"admin"}
{"cmd":"login","user":"admin","pass":"admin"}
{"cmd":"set_channel","id":0,"state":true}
{"cmd":"set_channel","id":0,"duty":0.99}
{"cmd":"set_channel","id":0,"duty":0.5}
{"cmd":"set_channel","id":0,"duty":0.1}
{"cmd":"set_channel","id":0,"state":false}
Yarrboard provides a websocket server on http://yarrboard.local/ws
JSON is sent and received as text. Clients communicating over websockets can send a login command, or include your username and password with each request.
Yarrboard provides a POST API endpoint at http://yarrboard.local/api/endpoint
Examples of how to communicate with this endpoint:
curl -i -d '{"cmd":"ping"}' -H "Content-Type: application/json" -X POST http://yarrboard.local/api/endpoint
curl -i -d '{"cmd":"set_channel","user":"admin","pass":"admin","id":0,"state":true}' -H "Content-Type: application/json" -X POST http://yarrboard.local/api/endpoint
Note, you will need to pass your username/password in each request with the Web API.
Additionally, there are a few convenience urls to get basic info. These are GET only and optionally accept the user and pass parameters.
- http://yarrboard.local/api/config
- http://yarrboard.local/api/stats
- http://yarrboard.local/api/update
Some example code:
curl -i -X GET http://yarrboard.local/api/config
curl -i -X GET 'http://yarrboard.local/api/config?user=admin&pass=admin'
curl -i -X GET 'http://yarrboard.local/api/stats?user=admin&pass=admin'
curl -i -X GET 'http://yarrboard.local/api/update?user=admin&pass=admin'
Yarrboard provides a USB serial port that communicates at 115200 baud. It uses the same JSON protocol as websockets and the web API.
Clients communicating over serial can send a login command, or include your username and password with each request.
Each command should end with a newline (\n) and each response will end with a newline (\n).
This port is also used for debugging, so make sure you check that each line parses into valid JSON before you try to use it.