Tag Archives: GQ-4X

Cheap prommer that works (GQ-4X) and one that doesn’t (TOP853)

I’ve had a few readers asking about the TOP853 eprom programmer and how I got it working. The truth is, I never did. Of all eproms I’ve tried, only a few 21V Mitsubishi 2764s have been successfully burnt. My conclusion and advice to everyone – don’t buy the TOP853 – it doesn’t work!

Here’s a quick list of what I tried before giving up:

  • tried several computers
  • different versions of Windows
  • different USB ports (1, 2 & 3)
  • different USB cables
  • a powered hub
  • various older versions of the software
  • modified an USB cable to draw extra current from the computer’s PSU

Unfortunately, nothing helped. I felt liberated the day I put the TOP853 in the trash and ordered a GQ-4X instead. It costs more than he TOP853, but on the other hand it works. I haven’t had one unsuccessful write yet. Other good GQ-4X features is that it supports modern 64-bit OS:es too, the software is in English instead of Chinglish and is frequently updated. I think the manufacturer is Canadian.

The GQ-4X can be found on eBay. Since I’m in the EU (Sweden), the best thing is to order it from another EU country. I bought mine on eBay UK from the seller cus_co_uk

Roland MKS-70 firmware update

I just upgraded the firmware in my newly bought MKS-70 from 1.03 to 1.08. I’m not actually sure what the differences are, but since I have the possibility to program EPROMs there was no reason not to.

However, the engineers at Roland decided to put the EPROM in a position that makes it impossible to pull it straight out.  The EPROM is located at the mainboard in the bottom of the MKS-70 and marked with an A. The two voice cards (same as used for the JX-10) are stacked upon that. It is possible to fold away those cards, but a lot of cables has to be detached. I should mention that there each voice card also has an EPROM, these are didn’t have to be upgraded.

The TOP853 couldn’t burn the TC57256D-20 EPROM that are used in the MKS-70 and JX-10. My advice is not to buy the TOP853 if your’re going to use it for programming. The GQ-4X did it after I added a custom line to a new text file called customdevices.txt


Name="TC57256D-20",ID="9845",Class="27256",WVPP="21V",Category="EPROM",MFG="Toshiba";