How to get Mitsubishi M5L2764's to burn on the GQ-4X everytime.

hailrazer

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How to get Mitsubishi M5L2764's to burn on the GQ-4X everytime.

Just an FYI for those of us trying to burn Mitsubishi M5L2764's on the GQ-4X

They are incredibly difficult to burn. A lot of times they won't even pass a blank check. I have over 40 of them from Nintendo VS boards and they were giving me tons of trouble. Only 1 in 10 would pass a blank check after "erasing" them. And those that did pass would hardly ever burn.

So in order to get them to work you need to open the devices.txt file in the GQ USB Programmer folder on your PC. Remove the following line:

Name="M5L2764",ID="XXXX",Class="2764(21V Vpp)",Category="EPROM",MFG="Mitsubishi",Message="Apply external power !";//by EZo

And add this line in it's place:


Name="M5L2764",ID="XXXX",Class="2764(21V Vpp)",Category="EPROM",MFG="Mitsubishi",VCC="5V",WVPP="21V",WVCC="6.2V",BVCC="5V",RVPP="5V",Message="Apply external power !";//by EZo

Then they will burn and blank check every time :)
 
was brought to this thread via another thread. Hailrazer, thanks for posting as I never thought about modifying these values. Learned something today.

The spec sheet for M5L2764 definitely says 6 Vcc +/- .25 for programming and the original value was setting it to a default 5.5 Vcc just out of that range. I guess, if you have trouble burning reading/burning a chip, check the info page for that chip and compare to data sheet to verify it is correct.

I was curious and started to play with the device text file. Looks like "Class" appears to be required and controls some of the default settings like code size, VPP but the rest is modifiable.
Name="MyTEST",ID="XXXX",Class="27C010";//Jacklick test

The syntax is at the top of the device.txt file but figured I would include.

; Syntax: Name="Device Name",ID="Device ID in Hexadecimal",Class="Class Name",Category="Category Type",MFG="MFG Name",Speed="Default Speed",Package="Package",Adapter="Adapter",CodeSize="Code Size",EepromSize="Eeprom Size",DIP="DIP Setting",VCC="Vcc",WVPP="Write Vpp",WVCC="Write Vcc",BVCC="Blank Vcc",RVPP="Read Vpp",Message="Message to User"
 
Replying to an old thread here, but I'm sure someone else will encounter this issue some day and need this. I also needed to write at the slowest speed and disable the "double write" option in the GQ software. Write errors went away once I made these changes.
 
I forget but I think my SuperproZ does those. it was one of the rom makes I pulled off Vs. boards. it's good that I have options.. I pulled a Motorola 2532 off a Pac board the other night and my GQ-4X doesn't have any Motorola rom support at all? :confused:
 
I posted this in another thread but figured it might as well correct/elaborate my post above here as well.

Because I hate talking out of my arse and had made some assumptions on the ability to change voltage to arbitrary values in the devices.txt file, I did some more research and testing.

Basically, as the help file states, there are 5 voltage settings for VCC and 6 for VPP.
VCC = 3.6v, 5v, 5.5v, 6.2v
VPP = 3.6v, 12v, 12.7v, 15v, 21v, 25v

In the GQ-4x, I believe there are two MC34063A DC-DC regulators/converters which steps up or down voltage as required. cool calculator on this chip / circuit http://www.nomad.ee/micros/mc34063a/

Anyway, bottom line is you can still modify the file but only to one of those supported values.

I also finally figured out the bug related to speed setting on these. In devices.txt file, speed 1 (slowest) == speed 5 aka -2 (slowest) in program; vice-versa speed 5 in devices.txt (fastest) == Speed 1 aka +2 in program. How they haven't fixed this is by now is beyond me.

For the more visual people, I made a quick video :)

 
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