MegaFlash issue

[00WReX]

Hi All,

I have spent the good part of a day mucking around with my MegaFlash.
To cut a long story short, I cannot write at all to the Winbond EEPROM. Reading is fine, no issues observed.
It was working fine a couple of days ago when the last thing I added onto it was SymbOS 2.1

Today I was looking at the X-mem flash tools and at one point accidentally had the write switch still enabled on the MegaFlash.

When i noticed it i switched it back and all appeared fine until I attempt any write including a park.
If I run any of the management software (RMA both BASIC & FutureOS as well as ROMAN), they appear to go through the normal write procedure, but when you check the ROM nothing has changed.

I have tried to completely erase/initialise the EEPROM, but absolutely nothing I have tried is
allowing  the MegaFlash to be written to.
And none of the contents change and all are still working as normal...I just cannot change anything.

I have fired up the CPC with no ROM's initialised and run RMA from disk, but did not help.

I have even swapped the Winbond chip with the SST chip on my FlashGordon and the problem follows the chip.

I then attempted to wipe the chip with my cheap chip programmer (came with a PLCC32 adapter), but it will not erase it.
Not sure if that is an issue with the cheap programmer (MiniPro TL866CS).
It will read the chip and SDP says it is has been disabled when I attempt to erase...but the data remains.

Within the last week, I have fired up the Amstrads after a bit of a break from them.
And I have been having nothing but problems...even had one of my CTM-644's blow on me.

Any thought's on the MegaFlash issue appreciated.

Cheers,
Shane

[gerald]

You may have locked your flash with the xmem tools.
You can explicitly lock/unlock it with RMA in the flash tool menu (where you can list/erase/swap).

[00WReX]

You may have locked your flash with the xmem tools.
You can explicitly lock/unlock it with RMA in the flash tool menu (where you can list/erase/swap).

Thanks Gerald,

Yes, I thought this may have happened as well.
But I have tried 'Init. Flash' under ROM management in RMA.
I also tried it under 'System Tools' on ROMAN.

Here is a quick rundown of what i have done...

My setup is...LowerROM connected with MegaFlash connected after it. Using RMA 1.45 for BASIC on a ROM on the MegaFlash.
A couple of day ago all was working normally...today I attempted to Park a ROM and found I was unable to write/modify the contents of the MegaFlash.
1)Tried to initialise the Flash via RMA and ROMAN.
2)Running FW3.15 on the lowerROM I hold ESC on boot to disable the ROMs then run RMA from disk.
3)Running FutureOS (Autoboot) on the LowerROM and running RMA for FutureOS off disk.
4)Removed the Winbond chip and booted the CPC with the MegaFlash connected.
  I plugged the chip in, then ran RMA from disk.
5)Removed the LowerRom completely so only the MegaFlash connected.
6)Tried RMA for BASIC v1.45, RMA for FutureOS v1.8 , ROMAN (v1 & v2).
7)Swapped the Winbond chip from the MegaFlash with the SST chip on the FlashGordon.
  The problem moved with the chip and the SST chip would erase/park when in the MegaFlash board.
  The Winbond chip in the FlashGordon behaved the same as the Winbond in the Megaflash.


Cheers,
Shane

[00WReX]

OK, something is plotting against me...

With my cheap IC programmer, it was the 1st time I had used the PLCC32 adapter.
While looking over it I just noticed a couple of solder terminations were shorting (buzzed it out with my MM).
I fixed that and was able to erase the Winbond chip.
I can also write ROMs to it with the programmer.....but I still cannot get any ROM manager to write to it from the CPC (and I am using the 'initialise flash option).

This is messing with my head 

Cheers,
Shane

[talrek]

ok i think i know where the problem is ;-)
if you use a Megaflash, then try this to "unlock" it under RMA !


- Go to initialize your EPROM
- When you put the switch on the Write position, put also the ROM 0 jumper on "ON", and THEN press a key
- don't forget the put the jumper "OFF" after writing


It should work. You can find more details on the "Absolutely Fabulous" RMA user's manual

[00WReX]

Ahhh talrek, where were you 8 hours ago 

Thank you very much...honestly I think I tried just about everything except placing the ROM 0 jumper to on while initialising the Flash.

Well everything except 'Read the Manual' it seems 

Thanks again...I think I almost wore out the PLCC socket today. 

Cheers,
Shane

[Bryce]

Ok, I'm way too late to this party, but yes, as Talrek said, you need to have ROM 0 jumper moved to init the IC, but you could also have used your programmers software to remove the lock bit. This should be an option in the software, the default for these programmers is usually to remove the bit before programming and reset it after programming.

Glad you got it working again though.

Bryce.

[00WReX]

Hi Bryce,

Yes, I attempted to remove the lock with the programmer as it has two 'tick' box's.
One says remove protection before programming.
The other says add protection after programming.

I removed the second tick, and looking at the work log it shows the SDP being removed and not being set on completion.
Prior to removing the tick i could see it being removed and added in the work log.

?? 

Buggered if i know...but the initialise flash with the ROM 0 jumper ON has definately done the trick.


Maybe I could ask TFM if he could put an 'onscreen' reminder in his next version of RMA so that when you select 'init flash' it prompts you to move the jumper.


Attached is a screenshot with the tickbox's in the bottom right...are they the same thing as the 'init flash'. ??


[attachimg=1]


Cheers,
Shane

[Bryce]

Yup, the tick boxes are correct, that should have solved the problem. You'd have to write something to the Flash with those settings of course, otherwise they don't take effect.

Bryce.

[00WReX]

Yes, definitely wrote to the flash with those settings.
And I could see/use the ROMs on the CPC that I had written with the EPROM programmer.
Just could not write to it from the CPC.

Ahh well...it's all back to normal now, that's the main thing I suppose.

Cheers,
Shane

[talrek]

You're Welcome !!!! I'm so glad to help someone on this forum as usally i'm the one who is helped 

[TFM]

Maybe I could ask TFM if he could put an 'onscreen' reminder in his next version of RMA so that when you select 'init flash' it prompts you to move the jumper.
Cheers,
Shane

Hi! Just saw this thread! Glad you got it working!    Ok, I will do that for the next update. Thanks for the hint. 

[00WReX]

Thanks TFM 

Cheers,
Shane