If you encounter problems with update, don't worry - the Loopsynth cannot be bricked permanently. The problems may possibly be caused by corrupted update files (empty files would be rejected but damaged files of correct size will be flashed but won't run) for example because of faulty SD card. Also, recently we accidentally released a version that turned to be incompatible with older units (s/n. below 1000) which soft-bricked the device.

Thankfully there is an online tool for flashing the ESP32 microcontrollers, compatible with various operating systems: esp.huhn.me. In modern operating systems things usually work right away, but depending on what edition of v2 you have, you may need to install drivers. Units with serial number below 1000 use FTDI chip and the drivers are usually already present in the system. Units with s/n. above 1000 use CH340G and may need drivers (e.g. in Windows), here is a guide how to install them (the same drivers are used as for the v1 Gecho).

How to tell if drivers are installed?

In Windows, check the control panel / Device Manager, you should see an USB Serial COM port (in my case as shown below it's COM31). Some other devices that you have installed in your computer may appear as COM ports as well. To find out which port is actually your Loopsynth, and to rule out the possibility that the port that you see is actually something else (e.g. when your unit was not detected because of the bad cable or missing drivers), check the device manager before connecting your unit, and see which new port appears after you connect it.

How to use ESPWEBTOOL

Connect your unit to the PC using the provided micro-USB cable and click "Connect" button.

You should see your COM port appearing in the dialog. Select it and click "Connect". In units with serial number below 1000, make sure that the power switch is in OFF position (programming mode). In newer units it is not important as the programming mode is selected automatically.

Check that the dialog appears on the top, confirming that the connection was successful.

Recover the original firmware

Delete 3 out of the 4 upload slots using the red bin icons, then change the remaining one's address to "1d000" (be careful about the number of zeros) and select the file to upload. You can download the required binary file from here.

In the following dialog, click "Continue".

You should see a progress bar and then this success message. You can reset your unit (in older version that means unplugging the USB, switching the power to ON, and plugging the USB back again).

If the above did not help

Sometimes after more than one update has been installed previously, the original firmware slot might have been overwritten and the method above is not sufficient. In this case, you need to re-upload the firmware completely. Click "add" to get one more upload slot, fill the 30000 to the memory location field (and double check that both memory locations are set correctly). Then upload the firmware file and click "Program". You need a specific firmware file for your unit, you can get it from the download page (the link is automatically created on the SD card), but if you cannot access it or you are not sure where to find it, ask us. If there is any problem with programming, make sure that the power switch is in OFF position (this applies to s/n. below 1000).

You should see a progress bar...

...and then this success message. You can reset your unit (in older version that means unplugging the USB, switching the power to ON, and plugging the USB back again).