Originally posted to r/tonalgym on Reddit.
Hey folks, I started a project to provide a completely custom controller for the Tonal 1. This replaces the Android tablet and directly talks to the motor controller using the internal USB serial connection.
This is super barebones and not well tested, so you’re on your own if it bricks your system. I figured I should publish it and see if folks were interested in contributing things such as workouts, programs, etc. The standard Tonal subscription is good enough for me, so I’m not sure how much I’ll actually push on this.
The code is at github.com/d4l3k/swolectl.
Photos
Architecture
Tonal is effectively two main pieces: an Android 6.0 system and app running on a MediaTek chip, and a motor controller with its own firmware running on a Luminary Micro microcontroller. These talk to each other using a simple protocol over a USB serial connection.
Most of the core weight features are actually implemented by the firmware on the motor controller and not the app. This makes it very easy to send commands to enable things like eccentric mode and others.
The protocol and firmware could potentially change down the line, so please be
cautious. I’m using firmware 5.2.18.0. Tonal seems to flash this at runtime
periodically, so even if they change it, you should be able to revert the
firmware as long as you have a copy of it.
Full details are in the protocol documentation.
Misc Findings
There seem to be a lot more exercise modes than are actually exposed currently. I’m curious what these do, especially perturbation, but I haven’t tested any of them. I’ve only tested features that are exposed by the Tonal interface.
| Value | Curve |
|---|---|
| 0 | Chains |
| 1 | Bell with eccentric |
| 2 | Reverse chains with eccentric |
| 3 | Chains with eccentric |
| 4 | Flat with eccentric (Smart Flex mapping) |
| 5 | Quadratic ascending with eccentric |
| 6 | Perturbation |
| 7 | Reverse chains |
| 8 | Eccentric reduction |
Connecting to the Motor Controller
To open the Tonal unit, there are four security hex screws on the right side of the unit hidden by the arm. Rotating it to the forward position with the arm extended is the easiest way to access them.
It is strongly recommended to power off your unit before doing anything to it.
The Android computer on the back of the screen has a white five-pin connector
labeled tablet on the bottom right. This connector exposes USB as well as a
wake signal to the Android computer. You can disconnect that connector and use
a USB connector instead. It’s also recommended to unplug the tablet power
connector.
Why?
I got accused of lying about rooting my Tonal because I don’t want to enable pirating the Tonal content and deal with all the legal implications. I pay for a subscription because I like the programs and the product.
I figured I’d make a better, fully local option that can be shared and can’t be patched by Tonal. If all you need is custom workouts and a better way of managing them, this is perfectly sufficient. I like the programs that Tonal provides, but it’s nice to have a completely offline option if Tonal ever goes out of business.
This is very much inspired by Valetudo for robot vacuums. Let me know if you try it out. I’m happy to help debug or troubleshoot.