Vecoven Upgrade Installation

SuperJX Flash Module

Fred Vecoven has released a new module that plugs into the ROM socket on the JX10/MKS70 assigner. It contains 16 or 32 bank cartridge feature all stored in non-volatile Flash memory. The size of available program space now allows Fred to take the SuperJX upgrades even further.



A built in bootloader facilitates easy upgrade of new firmware via system exclusive protocol and works seamlessly with the Roland or Vecoven M1024C cartridges giving huge storage potential similar to a modern synth.

All the features of the standard EPROM upgrades are included, notably the Faultless System Exclusive Implementation, Arpeggiator and Enhanced Replacement Display driver.

The Flash module looks deceptively simple, however the arrangement on the PCB is a very intricate combination of Software, Hardware and Programmable Logic.

It adds encrypted, writable non-volatile bank switched memory to a very archaic CPU in “Read Only” memory space. One interesting addition, is a crystal controlled digital timing arrangement that provides a work around for bug in the 6303 CPU that would otherwise prevent it working with modern fast memory devices.

All of these properties are essential in ensuring corruption free operation when loading and saving patches and executing the assembly coded firmware.


Installation is just a simple means of placing it where the old EPROM is on the assigner. A fitting guide is available on the Vecoven site downloads page.

The pictures below show the orientation and fitting position inside the JX10. For the MKS70 it is similar except the Assigner Board is underneath the Module Boards, a guide for removing them is here, although it is possible to change the firmware without removing the boards if extreme care is taken.


If the capacitors nearby touch the module then gently push the first two rows over slightly, before pressing the module gently into place as shown below:

As can be seen from the pictures above, it is not necessary to remove the flat cable if you are careful.

Running New Firmware

This section is applicable for ROM firmware upgrades as well as SuperJX Flash module.

Factory Reset

New firmware uses more new memory locations for settings that the Roland firmware does not. So when the upgraded software tries to use what it thinks are valid settings from previously unused memory that has random values allocated, it gets confused leading to voices not working or very strange midi settings that look correct but are in fact not.

The Vecoven “factory reset” function, formats the area for the configuration settings correctly, after which enter the MIDI menu and adjust the settings to what you want. It doesn’t clear the tone or patch settings.

Factory reset is executed by the following sequence:

  1. Power Off
  2. Write protect Off
  3. Hold [WRITE] and [ < ]
  4. Power On & Wait for patch display to appear
  5. Release [WRITE] and [ < ]
  6. Edit the settings under [MIDI] that you want
  7. Press [WRITE] followed by [ENTER] to save settings

Factory Reset – Alternative

Another way without using memory clear, is to go through all settings under “midi”, one by one, changing them by rotating the alpha dial clockwise and anticlockwise regardless of what they show on the display.

Before these operations it is vital that the memory protect switch is set to “Off” otherwise they cannot be stored.

After either of these operations, press “Write” followed by “Enter” to copy the new settings into working memory.

Display Reset

The results of an incorrect display setting are that the Roland standard display is blank. The SuperSynthProjects display will work normally in this situation but may have the wrong brightness level.

Sometimes the memory can be scrambled in such a way that the “GU280 SUPPORT” is selected. Also, it might be that a user has set the parameter by accident when they only have a basic Roland display.

Display reset is executed by the following sequence:

  1. Power Off
  2. Write protect Off
  3. Hold [Enter]
  4. Power On & Wait for patch display to appear
  5. Release [Enter]
  6. Press [MIDI] check that GU280 SUPPORT is set to “OFF”
  7. Press [WRITE] followed by [ENTER] to save Midi settings

If using a SuperSynthProjects display, do not switch off power for at least 30 seconds so that it can learn what firmware you have installed.


Originated 2017, Copyright 2019 Super Synth Projects: Guy Wilkinson & Fred Vecoven