Firmware updates 856 for ZELLERSASN

Upgrading firmware:

This page contains instructions and links to the latest firmwares. Please be aware that not all firmwares are compatible with all board revisions. For the purposes of the update files and procedure we call the 2 versions of the pedal V1 and V2. They are easy to tell apart as follows. V1 has no expression or midi through. V2 has midi through and an expression jack.

Prerequisites:

1. A windows based computer.
2. A usb A to usb mini B cable
3. An 856 for ZELLERSASN pedal.
4. STM Dfuse software available (free) here .
5. Firmware file (.dfu)

Currently available firmware

1. Firmware 1.6.4 for V2 units. This is the latest firmware. This file is compatible with the V2 units (units with expression jack and midi through connector). The manual for this version is available here
   
2. Firmware 1.2 for V2 units. This is the firmware that shipped with the majority of the V2 units before mid 2019. The manual for firmware 1.2 is available here.

Procedure:

1. Please note that updating the pedal will wipe its presets.
2. Unzip and Install the STM Dfuse software and restart your computer if necessary. 
3. Locate and load the program "Dfuse Demo (v3.0.6)". It should have the following path by default "Program Files (x86)\STMicroelectronics\
   Software\DfuSe v3.0.6."
4. Disconnect power from your 856.
5. Locate the mini USB jack which is just below the DC jack on the back of the pedal.
6. Connect the usb cable to your computer and the pedal.
7. Apply 9V power to the 856. The usb cable must already be in place before powering up in order to communicate with the computer. Ie make sure steps 6 and 7 are done in the correct order. Windows may detect the device with just the usb connector plugged in, we recommend however also powering it with 9v for more reliable programming.
8. Windows should now detect the device. Allow windows to automatically find the driver online, it may take several minutes the first time you connect the pedal to your computer.
9. Once the device is properly initialized go back to Dfuse Demo and click on the "Choose" button that is under the "Upgrade or Verify Action" section of the window (lower right). A window opens and you must select the firmware. Locate the firmware you downloaded with the .dfu extension from step 5 of the prerequisite.
10. Click on the "Upgrade" button just beside the "Choose" button you used in step 9. A warning will come up about how the device is plugged in in dfu mode and it is impossible to know if the file is correct for the device... Click yes to continue anyway. Two things should happen in the progress bar now, first an erase, then an upgrade. Once the upgrade completes, disconnect the USB cable and power, and exit Dfuse. The unit is now updated but needs to reboot.
11. Disconnect the USB cable from the 856. Then disconnect and reconnect power to reboot the pedal. It will now be updated.