Burning Nvram ram tune onto my Vn memcal

[pman92]

If it's not reading the ID there is something wrong. It's never going to read or write properly. You need to sort that out otherwise you're wasting your time trying anything else.

No you cannot properly read or write the NVRAM without removing it from the socket.

[Charlescrown]

You guys are correct. I just powered up an old laptop and put in 27C256 and pin 7 is in red so it's obviously an indicator where the chip is to be inserted.

[delcowizzid]

Turn thr write speed down to 0 or minus 2 and try.
To erase it 6 minutes is plenty if the window is within 10mm of the light tube too long and you will effect the speed of the eprom and the ecu will fail to run

[Asho88]

Yeah I was playing around with that but usually after I’d tried doing at full speed the program has been playing up so going to try a different laptop this one is running windows 10 was needed to pick up the Nvram. I’ll got my other one which has wivdows 11 and try that just cause I can. I noticed that when it attempts to write it’s actually writing to it but then failing which previously don’t think it was writing anything. Also getting another memcal and computer to try.

[vlad01]

You can try manually selecting the ID as SMJ27C512, the manufacture comes up as ASI Semic for the VR auto chip on my T48.


My GQ-4X died the last xmas. I had only used it maybe 25-50 times max, even though it was from 2013 or 2014, so maybe age? Just had weird driver issues that couldn't be explained by drivers alone. It actually died half way though a burn iirc, read fine just prior to the burn. I would occasionally get the red light on the VCC iirc, but most often it was green like yours. I vaguely recall it would connect to the software, but always lost the entire programmer after attempting to write and you needed to restart windows for it to see it again or maybe it was reinstalling the software due to some driver error.

I bought the T48 and found it better in every way and much cheaper too. After seeing how many members have lost their GQ-xx programmers, I wouldn't be surprised if it's just another statistic. They seem to die in really weird ways from what I have seen.

If you have another VN -VP 128k chip, you could run an experiment and read the content, erase, and rewrite it to prove or disprove what the problem is.

[Asho88]

It’s only 12-18 months old I reloaded my Nvram 2-3 times it’s had barely any use. But it is weird but also I’ve never burnt to a memcal so I have no idea just figuring it all out been a frustrating process so far lol. I was told the memcal was 100% a Vr V6 auto but I can’t be 100% though it is different to my Vn v8 one. I naively removed the sticker and lost it so can’t confirm. The numbers on it say it’s a VN-VP chip but is definitely different.

[vlad01]

The bottom of the chip has the chip number, but you'll have to desolder it to see. Mine said L27C512U, but ID's as the SMJ27C512.

I tried the AMD ID originally but it said it wasn't a match and gave me that instead, which that IDs perfectly when selecting it from the start.

I think some of the early EPROMs on VN were AMD ones, but most of mine aren't marked with a brand, so the ASI Semic might be the right one going by the ID match.

[antus]

When you get another chip, get it reading first. It proves the general function and connectivity to the computer and the connections to the chip (with the exception of the program pin and program power).

[Asho88]

Yeah I will I’ll be hesitant to erase it. So I found both stickers the Vr one is apparently a Vn v6 one lucky I got it for free still having issues though even trying to burn the stock tune on 16kb gets to 3% and crashes. I’ll try the other laptop and try to chase up the Vr ecu and memcal I have lined up.

[pman92]

Attached is the list of chip ID to part numbers.

The factory memcals used a few different part numbers, even for chips the same size.

Also can recommend getting a T48. They're cheap as chips and work great. And I haven't heard anyone have problems with them or have them fail like the GQ4X4