TouchDRO started as a DIY project back in 2012, and we still do our best to support the DIY community. As the TouchDRO hardware has grown in complexity, though, the path of least resistance for most builders is now the DIY TouchDRO Kit (TDK-40, mostly assembled, with all the input-conditioning circuitry already done) or, for those who want to design their own carrier board, the pre-programmed TouchDRO module.
Both options ship with the firmware already flashed, so you skip the programming step entirely. More importantly, they include the full TouchDRO Plus feature set — workflow automation, CAD/photo overlays, advanced probing, CSV import/export, and so on. The free firmware on this page runs the TouchDRO Community app, which covers the core DRO functionality but does not include the Plus features and is limited to basic quadrature A/B scale inputs (no SPC or BIN6 serial protocols).
For the latest build instructions and a side-by-side comparison of DIY vs. pre-assembled options, see the DIY DRO Build Guide.
The current 32-bit free firmware (V3.2) is built for the Espressif ESP32-DevKitC-32E module, and supports basic quadrature A/B scale inputs. It pairs with the TouchDRO Community app and follows the pinout documented in the DIY DRO Build Guide. The free firmware does not include serial protocol support (SPC, BIN6) or TouchDRO Plus features — for those, use a pre-programmed TouchDRO module.
| Version | Description | Release Date | Files |
|---|---|---|---|
| 3.2 - Current | Free firmware for ESP32-DevKitC-32E. Quadrature A/B only; pairs with the TouchDRO Community app. See the flashing instructions in the DIY DRO Build Guide. | Mar 2025 | zip |
| 1.6 - Legacy | Uses a different pinout and is not compatible with current
ESP32-DevKitC-32E builds. Provided for older self-built ESP32 adapters (2022–2023).
Build docs: Legacy DIY DRO
Reference. Fixed timing for iGaging EZ-View Rev. 1.7B Updated negative bit for Shahe scales USB output no longer requires Bluetooth connection |
Mar 12, 2023 | zip |
| 1.4 - Legacy | Uses a different pinout and is not compatible with current
ESP32-DevKitC-32E builds. Initial release for ESP32 DIY adapter. Build docs: Legacy DIY DRO Reference. |
Oct 31, 2022 | zip |
This version of the firmware supports classic iGaging DigiMag and AccuRemote DRO scales. It is the same firmware that comes pre-installed on the TouchDRO Adapter for iGaging Scales, TouchDRO Adapter for Shahe Scales, and TouchDRO DIY DRO Adapter Kit.
| Version | Description | Release Date | Files |
|---|---|---|---|
| 2.4 | Stability and performance improvements. | Jan 18, 2021 | ti-txt |
| 2.0 | Added support for Shahe 5403 and Absolute DRO+ scales; better tachometer resolution. Note: This firmware outputs scale clock on each clock line as opposed to pin 1.7 |
Oct 10, 2019 | ti-txt |
| 1.31 | Added support for the tachometer; improved scale clock stability | Jan 11, 2015 | hex, ti-txt |
| 1.2 | Updated the code to be pin-compatible with the Mixed Scale version | August 24, 2013 | hex, ti-txt |
Supports Glass and Magnetic DRO scales with quadrature output and has same functionality as the firmware that ships pre-installed on the TouchDRO Adapter for Glass Scales
| Version | Description | Release Date | Files |
|---|---|---|---|
| 1.2 | Added support for touch probe | Jan 31, 2016 | hex, ti-txt |
| 1.1 | Added support for the tachometer and 1 micron scales | Jan 11, 2015 | hex, ti-txt |
| 0.1 | First release | November 19, 2013 | hex, ti-txt |
This firmware supports iGaging DigiMag/AccuRemote "Remote DRO" scales as well as inexpensive calipers and 48 bit Sylvac-type Chinese scales.
| Version | Description | Release Date | Files |
|---|---|---|---|
| 1.0 - Recommended | Stability improvements. | January 18, 2016 | hex, ti-txt |
| 0.3 | Added support for tachometer, and clock output for iGaging Digmag/Remote DRO scales | July 10, 2014 | hex, ti-txt |
| 0.2 | First release | November 24, 2013 | hex |