2500 JJOS-XL - Flash ROM write error ??

Hi fam,

Sorry, but it will be a bit long...

Just yesterday I've installed JJOS-XL 3.57 on my 2500 to test it out and - to my horror - I got "Flash ROM write error" message.
It always shows up when I boot the MPC with [ERASE] + [Power] pressed and sometimes when I access different modes, for example REC: [Mode] + [PAD 4]. Error is shown for a short while and disappears. If it's going to stay like that it's not THAT much of a problem, but now I'm afraid to buy JJOS-XL in case it gets worse. This only applies to JJOS-XL, no problems whatsoever with AkaiOS/Free JJOS.

There are some threads about this issue on the forums but no one ever really followed up on how the things ended up - it would be great if by any chance someone who had this issue in the past could elaborate on the topic?

My questions/concerns about the problem:

1. Why this error shows ONLY on JJOS-XL and not on AkaiOS/Free JJOS?
It makes me think there may be some bug in JJOS-XL for 2500 (as it doesn't seem to be reported by 1000 users). I mean if the Flash ROM is faulty (as JJOS-XL suggests) why there are no problems on AkaiOS/Free JJOS?

2. Does anyone knows is it possible to just replace the Flash ROM chip on the motherboard PCB (de-solder the old one and solder a new chip)?
Manual on p. 114 states that: "The global settings found in the MPC2500 (listed below) are saved to the internal Flash Memory and stored when the MPC2500 is turned off. You can re-initialize the Factory Preset settings using the following procedure: 01. Turn the MPC2500 on while holding the [ERASE] key (...)"
So it seems that BIOS/OS are in some other chip so it should be possible to solder a new flash ROM if it "just" stores global settings and not OS, but on the other hand it should probably be pre-programmed with factory presets.


I will do some more testing today after work and post the results in the evening/tomorrow.

If you have any advice I'm all ears!

Cheers.

It is possible to swap out the Intel flash on the mainboard provided you have the tools and skills to do so but replacing it with a blank Intel or compatible flash won't be enough.

The OS is stored on the flash so I'm not sure what lead you to believe otherwise? There are no other identifiable flash chips on the mainboard.

So fashing back to the stock Akai OS does work for you -- Just so we're clear, did you first upgrade to the JJ OS free and then upgrade to JJOS XL?

Thanks for the reply @richie - I've managed to solve the problem (or it has solved itself ).

Here is what I did:

1. I've tried reinstalling all OS'es in this order: first Akai OS, then Free JJOS and lastly JJOS-XL ver. 3.57.
Nothing has changed - no problems on Akai OS or Free JJOS and still "Flash ROM write error" on JJOS-XL. I was holding [ERASE] button every time when booting MPC after OS change.

2. I went back to Free JJOS so I could access "Internal Memory" in Save Mode.
I did that because I remember that when I installed JJOS2XL on my 1000 and went back to Free JJOS there were strange characters (instead of letters) in program names stored in "Internal Memory" . On 2500 I had a lot of "(Unused).PGM" files in "Internal Memory". I created one program BLANK.PGM with almost 5MB sample assigned to pad A01 and saved it to "Internal Memory".

3. I am not sure if I did this (too much OS reflashing) but I think I installed JJOS-XL ver. 3.57 again and the error was still there.

4. I downloaded older JJOS-XL ver. 3.48 from MPC-Tutor's site (https://www.mpc-tutor.com/mpc-operating-systems/) and installed it.
Surprisingly - when I was booting the MPC with [ERASE] button pressed down - there were no errors. Also when I was changing modes (REC, TRIM, etc.) there were no errors.

5. I installed JJOS-XL ver. 3.57 - no errors this time!!!


It's hard to pin point which of these steps helped (if any). My bet would be it was installing older JJOS-XL first and then the newest one, but there are too many variables which come into play to tell for sure.

As for the error I think it might be some old unsolved (or even not recognized by JJ) problem with JJOS or maybe OS update procedure. I mean it's damn strange that people were reporting to have the exact same issue back in 2014 - everything works fine and after switching to JJOS-XL - bam! - "Flash ROM write error". And if it's a problem with Flash ROM - how the hell it shows up only in JJOS-XL but both Akai OS and Free JJOS work without problems?...
If i find time I'll try to carry out some more tests because without a repeatable procedure to cause the error every time it's just guessing.


One more (important) thing: before I solved the problem I wrote down the Product ID from the Save screen and checked it again later when the error was gone - the Product ID is different now. It's the same now every time I boot my machine, but it was different when error existed. So I strongly recommend to check if JJOS2XL (for 1000) or JJOS-XL (for 2500) works properly BEFORE buying the password, so you won't end up with the useless password due to wrong Product ID.

Hopefully this will be of some use if anyone encounter "Flash ROM write error" in the future .

Cheers!

Thanks for taking the time to write a detailed response. Hopefully others will find it of use.

I remember reading some years ago that were was a process to upgrading to JJ OS XL where users were told to first upgrade to free and subsequently upgrade to the newer OS. I believe it had to do with a re-write JJ did where essentially you got the core OS on the free version and then an update patch to the newer registered OS.

In the same token, there was some mention about product ID issues if you did not upgrade in the suggested sequence of Akai OS -> Free -> Latest OS. -- Likely due to a new way of addressing which was causing inconsistencies if the upgrade sequence was not followed (So XL would be looking on the flash for specific data and was being read back garbage as the flash layout was changed and did not coincide with what it was looking for (if I explained that strange, let me know and I'll re-write this response in a more coherent manner hopefully).

I didn't have the issues you had because I am an older JJ OS user from 09 so I've continually updated and updated over the years. I remember seeing someone managing to accidentally glitch JJ OS into being registered without purchasing a key due to not following the upgrade process correctly. Once word got out about that, there was something about JJ changing the key process to 'fix' that 'issue'.

For anyone else struggling with this like I was just now:

I had XL installed and when I started up it would display 128mb ram installed, then JJOS XL for a second, then "Flash Rom Error" before making it to the main screen.

I tried a different variation of what was suggested here.

I tried to just flash the Free JJOS and the XL back and forth for a bit with no luck. For a minute I thought I'd have to live without JJOS XL.

I then reinstalled Akai OS 1.24, then JJOS 3.13, then JJOS XL and then it seemed to work. I didn't think it was a motherboard issue because everything worked fine on the akai OS and the free JJOS.

Any way, stress relieved. Hope this helps.

If anyone else is struggling with this. I had the same problem.
Removing the CD from my drive while installing and first time after startup solved it for me!
Now I can also use the CD drive again without problems.

Circusbeer wrote:If anyone else is struggling with this. I had the same problem.
Removing the CD from my drive while installing and first time after startup solved it for me!
Now I can also use the CD drive again without problems.

Dope, thanks for sharing that. I'll put it in my notes for the future man.

God bless you

Hamsta Gangsta wrote:2. I went back to Free JJOS so I could access "Internal Memory" in Save Mode.
I did that because I remember that when I installed JJOS2XL on my 1000 and went back to Free JJOS there were strange characters (instead of letters) in program names stored in "Internal Memory" . On 2500 I had a lot of "(Unused).PGM" files in "Internal Memory". I created one program BLANK.PGM with almost 5MB sample assigned to pad A01 and saved it to "Internal Memory".

going through the same issues with my 2500 and while i've tried the basics of everything in this thread so far, i haven't tried the BLANK.PGM trick yet. i sort of suspect that's what will be needed to overwrite incomplete or missing data on the flash ROM. i'll follow up if i'm successful, but in the meantime, this is frustrating.

As in every machine i came across so far: Just avoid using INTERNAL MEMORY at all costs. Almost every time someone uses it, it leads to errors and failures in the future.

Hamsta Gangsta wrote:Thanks for the reply @richie - I've managed to solve the problem (or it has solved itself ).

Here is what I did:

1. I've tried reinstalling all OS'es in this order: first Akai OS, then Free JJOS and lastly JJOS-XL ver. 3.57.
Nothing has changed - no problems on Akai OS or Free JJOS and still "Flash ROM write error" on JJOS-XL. I was holding [ERASE] button every time when booting MPC after OS change.

2. I went back to Free JJOS so I could access "Internal Memory" in Save Mode.
I did that because I remember that when I installed JJOS2XL on my 1000 and went back to Free JJOS there were strange characters (instead of letters) in program names stored in "Internal Memory" . On 2500 I had a lot of "(Unused).PGM" files in "Internal Memory". I created one program BLANK.PGM with almost 5MB sample assigned to pad A01 and saved it to "Internal Memory".

3. I am not sure if I did this (too much OS reflashing) but I think I installed JJOS-XL ver. 3.57 again and the error was still there.

4. I downloaded older JJOS-XL ver. 3.48 from MPC-Tutor's site (https://www.mpc-tutor.com/mpc-operating-systems/) and installed it.
Surprisingly - when I was booting the MPC with [ERASE] button pressed down - there were no errors. Also when I was changing modes (REC, TRIM, etc.) there were no errors.

5. I installed JJOS-XL ver. 3.57 - no errors this time!!!


It's hard to pin point which of these steps helped (if any). My bet would be it was installing older JJOS-XL first and then the newest one, but there are too many variables which come into play to tell for sure.

As for the error I think it might be some old unsolved (or even not recognized by JJ) problem with JJOS or maybe OS update procedure. I mean it's damn strange that people were reporting to have the exact same issue back in 2014 - everything works fine and after switching to JJOS-XL - bam! - "Flash ROM write error". And if it's a problem with Flash ROM - how the hell it shows up only in JJOS-XL but both Akai OS and Free JJOS work without problems?...
If i find time I'll try to carry out some more tests because without a repeatable procedure to cause the error every time it's just guessing.


One more (important) thing: before I solved the problem I wrote down the Product ID from the Save screen and checked it again later when the error was gone - the Product ID is different now. It's the same now every time I boot my machine, but it was different when error existed. So I strongly recommend to check if JJOS2XL (for 1000) or JJOS-XL (for 2500) works properly BEFORE buying the password, so you won't end up with the useless password due to wrong Product ID.

Hopefully this will be of some use if anyone encounter "Flash ROM write error" in the future .

Cheers!

Thank you. This was very helpful. I had the same Flash ROM write error issue. I just went to MPCstuff and was able to get an older version of JJOSXL - version 3.61. I flashed back to akai OS. Then I reinstalled JJOS Free.

One key thing is that I held erase every time I booted this time. I did not the first time because I was following the JJOS install video and it said to do that later in the video. I am not sure if that was a factor as well.

But to be safe, always hold erase when powering up after a firmware flash.

I installed OS XL 3.61. It worked. I flashed to 3.88, again held erase and powered up and now it works fine. No Flash ROM error. I just sent my product ID to JJ so I can buy XL next.

Hopefully this helps someone out as well.