A firmware update for the Roland Jupiter 6 Synthesizer

    Someone recently suggested that I add sysex patch save/load and non-volatile storage of MIDI channel to the Roland Jupiter 6 firmware.   At first I was reluctant to do anything with the Jupiter 6, due to the existence of the popular Europa modification.  But since the Europa kits are currently difficult to get, it seemed that a much simpler firmware upgrade might be of interest to some people.  Even though the JP6 has a full set of controls, I thought some people might like to have CC control of settings.  And as the project progressed, a few other features were suggested and added.

    My new firmware (which used the V6 code as the starting point) has been tested by three JP6 owners, and is now available.   Here are the new features:

1) MIDI Sysex patch and patch preset save and restore - saves or restores entire tone RAM (all 48 patches and 31 patch presets) in one operation (tape save/load works as before)

2) MIDI CC parameter changes are now supported.  Separate control of upper and lower voices in split mode for most parameters.    (No CC's are transmitted)

   Maximum rate for CC reception is two per 19 mSec period, which is approximately 105 CC's per second.   If CC's are sent faster than this, some will be dropped. 

3) Non-volatile storage of MIDI channel and user settings

4) User settings for the following:

a) Mod wheel CC destination can be any one of the following:

VCO mod by LFO1 amount

VCF cutoff mod by LFO1 amount

VCA mod by LFO1 amount

LFO1 rate

XMOD manual amount

Pulse width

VCF cutoff

VCF resonance

b) Arp can be clocked by MIDI instead of internal clock, with five divider settings

    Can be configured to require Start/Stop, or just free-run

c) Factory patches and patch presets can be read from the EPROM instead of user patches in RAM.

   (User patches are not changed)

d) "All notes off" MIDI messages sent by original code every time the last key was released can be disabled.


5) Arpeggiator "Down then up" mode has been changed to a random arpeggiator mode.

6) VCO waveform buttons now toggle, making it easier to enable multiple ones.   They can all be turned off.

7) VCO sync can now be set to "both ways" although this doesn't seem particularly useful

Note: This is *not* a firmware-only equivalent of the Europa mod.  The Europa MCU runs at twice the speed of the original JP6 MCU.  And the Europa firmware was a complete re-write of the JP6 OS.   My firmware adds some new features to the Roland V6 code.  It runs at the same speed as the Roland code.

  The original Jupiter 6 firmware EPROM was full, so no room for any new code.   To allow using a larger EPROM, it was necessary to design a small daughterboard which plugs into the existing EPROM socket.  A single wire needs to be soldered as well.   (It is not necessary to make any modifications to the bottom of the JP6 pc board., and no traces need to be cut)  Here is how it looks after installation:  (The EPROM window would normally be covered)


As noted above, MIDI CC reception is now supported for controlling patch parameters.   Here is a document containing the CC assignments, along with some additional information about using the new firmware.   Here is more or less the same information presented in a different format.  (This document was created by a user of the new firmware and sent to me. Thanks)

I am offering a blank pc board plus the parts needed to assemble it (including a programmed EPROM) for $80 plus postage.  Please contact me if you are interested.  I will not be offering assembled boards.

Here is a document showing the steps required to install the new firmware.

  Please note: Taking a Jupiter 6 apart and installing the new pcb must be done carefully, or damage to the synthesizer could result.  It should only be attempted by someone familiar with this type of work.  I will not be responsible for any damage to any instrument caused by either proper or improper use of the code offered here. 


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