MegaFlash Released!

[Bryce]

Hi 00WReX,
       as the effects of the last beer starts to wear off, something just occured to me: To write ROM0 to the MegaFlash you have to use a slightly different process:

1 - Boot the CPC with the ROM0 Jumper in the OFF position.
2 - Do all the next steps with the ROManager as usual.
3 - When the ROManager tells you to switch the MegaFlash to write mode, you need to move the ROM0 Jumper, then switch to write mode and press any key.
4 - When it starts beeping switch back to read mode and restart the CPC.

Is this the process you've used?

Bryce.

[00WReX]

Ahhh Bryce, yes...got it working and no I was not using this procedure...I was not aware that I had to move the jumper to the right before writing ROM 0.
Excellent, that was doing my head in. I'm sure you've said it somewhere before, but I did not remember it.

And it still was not straight forward...

Seeing your post I got all excited...tried it straight away and same result (BASIC version of ROManager)...then tried FutureOS version...same.

Sh!t...then I thought of trying QuickCMD again and it worked...not sure what the story is with all that, and I will try again with ROManager, but hey I'm happy. Thanks again.

So now my 6128 that has Basic version 1.20 onboard is running Basic version 1.23 from the MegaFlash with the boot message changed to reflect this. Just for fun and because you can 


Cheers,
Shane

[TFM]

So it all works? Glad to hear that!!! 

[00WReX]

Hi Guys,

My testing continued today as I had the day off work...this is what I have noticed...

Using Bryce's described method above for writing to ROM position 0 on the MegaFlash,

If I load up a BASIC file onto ROM 0 in Binary form via QuickCMD  the CPC boots fine off  the Megaflash ROM 0 on reset.
If I load up a BASIC file onto ROM 0 in ASCII form via ROManager for FutureOS  the CPC boots fine off  the Megaflash ROM 0 on reset.
If I load up a BASIC file onto ROM 0 in Binary form via ROManager for BASIC  the CPC cyclic reboots on reset.

But, this is what I have observed...

With FutureOS parked, I can load up a BASIC file onto ROM 0 in Binary form via QuickCMD.
Exit out and reboot the CPC and all is fine (CPC boots off the MegaFlash ROm 0).
If I un-park FutureOS (activate it) and exit from ROManger and then reboot, the CPC cyclic reboots and it appears that ROM 0 gets corrupted (Calculated
Checksum is different before and after activating FutureOS).

If I go in the other direction, and use ROManager for FutureOS, I can load up a BASIC file onto ROM 0 in ASCII form.
Exit out and reboot the CPC and all is fine (CPC boots off the MegaFlash ROm 0).
Now if I park FutureOS (de-activate it) and exit from ROManger and then reboot, the CPC cyclic reboots and it appears that ROM 0 gets corrupted
(Calculated Checksum is different before and after activating FutureOS).

So to cut a long story short, If I have ROM 0 activated via the jumper on the MegaFlash, and I Park/un-park (disable/enable) futureOS, it appears that
the ROM 0 gets corrupted, and this appears to be confirmed by the before & after Calculated Checksum.

UPDATE 1:
To prevent the ROM 0 corruption, prior to Parking/un-parking the FutureOS ROM make sure that the ROM 0 jumper on the MegaFlash is set to OFF (the left hand side position).

UPDATE 2:
OK it appears that you need to move the ROM 0 jumper to off prior to any writes to the MegaFlash, otherwise ROM 0 gets corrupted.


Hope this all makes sense,
Cheers,
Shane

[TFM]

Hi,

Well, I know that there is a chance that ROM 0 write-enabled could cause problems (in it). But in the next update of the ROManager this will not be a problem any longer (therefor 1.44 works). I'm curious that QCMD ins not having the same troubles (I'm too lazy to check its code though). However after the next update everything shall be fine.

Here a BIG THANK YOU to SyX for helping and testing nearly endless to fix the last bug.

Now to explain the problem. The Basic version switches Basic on after the write cycle, this may corrupt some bytes there during the wait-time for the keypress. In the update the CPC banks to a DEAD zone, so unexpected write cycles go into the DEAD zone and everything is fine.



ADDON: Parking and Unparking can corrupt ROM 0, that's true. But it does not matter if FutureOS is parked or not, because FutureOS doen not interact with the native CPC-OS. It just provides an RSX command for starting it. It does not alter the CPC-OS.

UPDATE 1:
To prevent the ROM 0 corruption, prior to Parking/un-parking the FutureOS ROM make sure that the ROM 0 jumper on the MegaFlash is set to OFF (the left hand side position).

Parking FutureOS? That's blasphemy

UPDATE 2:
OK it appears that you need to move the ROM 0 jumper to off prior to any writes to the MegaFlash,

That's absolutely correct, but in ROManager 1.44 the bug is killed :-)

[00WReX]

Thanks TFM, apprciate the reply.

Actually you will be pleased to know that FuturOS is permanently on the MegaFlash now and active all the time (I will not park it anymore I promise  ).

But, you may not like this part  ...
To have FutureOS permanaently activated I needed to change the bootup colour scheme as for me personally I did not like the original colour scheme.
I must be getting boring in my old age, but I settled on the basic original blue & yellow colours.
I did also try another simple text only colour change, but boring blue & yellow it is for me. Attached are the pictures of my changes.
I will not post the changed files, because I'm sure you don't want edited files floating about (I did only change the colours though).
The files will be for my personal use only  .

Cheers,
Shane

[Bryce]

Glad you got it all working. And good to know that it's not a Hardware problem, or that your device got damaged on its way to Australia

Bryce.

[TFM]

Thanks TFM, appreciate the reply.

Actually you will be pleased to know that FutureOS is permanently on the MegaFlash now and active all the time (I will not park it anymore I promise  ).

You make me the most lucky man today! Well appreciated 

But, you may not like this part  ...
To have FutureOS permanaently activated I needed to change the bootup colour scheme as for me personally I did not like the original colour scheme.
I must be getting boring in my old age, but I settled on the basic original blue & yellow colours.
I did also try another simple text only colour change, but boring blue & yellow it is for me. Attached are the pictures of my changes.
I will not post the changed files, because I'm sure you don't want edited files floating about (I did only change the colours though).

Thanks' a lot for your feedback!!! I will add your thoughts to my To-Do list right now! Guess I will change the installer in a way that allows the user to change colors (and even the beep).

I will not post the changed files, because I'm sure you don't want edited files floating about (I did only change the colours though).

Well, it's ok for me if your release some "updates". But what I really like is the fact, that you share your thoughts. So things can get better and any comments are appreciated    (And if changes take time, then it's not stubbornness, just lack of time).

[00WReX]

Thanks again TFM,
I'm constantly impressed by what you and others are able to achieve (both Software & Hardware) with the humble CPC.
And your passion for the CPC is obvious, and would never call you stubborn...I fully understand trying to find the time is the hardest part.
I am also very busy with my work and have 3 teenage kids that are often in different places all at once...I feel like a taxi service 



Cheers,
Shane

[TFM]

Well, if the kids are nice and wash the car, then you can let em play R-Type on the CPC 

However, coming back to the MegaFlash. My weekend didn't work as expected, and I'll be busy next week, so the update to ROManager 1.44 will take some more time. However Bryce will help me in testing one of the new functions (Switch Software Data Protection OFF), if it works we can do even this on a real CPC now. (BTW. The SDP must be switched off once if you install a new Flash memory).

[Bryce]

Alas, my stock of MegaFlashes has finally come to an end. However, I will continue collecting names of people interested in having one and might consider a second batch later this year.

Bryce.

[Gryzor]

Nahhh it's good as it is, this way ours will be worth more in a few years' time

[TFM]

Nahhh it's good as it is, this way ours will be worth more in a few years' time

Don't worry, the second batch will get an ugly red icon or something disturbing ;-) Well, at least if we ask Bryce very nicely 

[Bryce]

I actually ordered a few more MegaFlash PCBs when I was ordering the LowerROM PCBs, so I have a few more if anyone still wants one. They are identical to the original boards, so I will have to investigate methods of adding a huge ugly red icon to keep you happy

Bryce.

[TFM]

Well, I know this is getting a bit off topic now, but.... Great to hear that you ordered the LowerROM PCBs :-)))

[Bryce]

There's a thread for it here http://www.cpcwiki.eu/forum/amstrad-cpc-hardware/lowerrom-swapper/ , with pictures

Bryce.

[TFM]

Thanks' friend, just saw it. I'm still pretty sick, so my brain doesn't work well. Already emailed you :-)))

[TFM]

Well.... maybe slowly it's getting time to a second batch of MegaFlash cards? Any interrest? Please post here.

[Bryce]

I still have a few MegaFlashes available, so anyone interested can just contact me with a PM. No futher batches are required yet.

Bryce.

[Gryzor]

...and now I'm tempted again.

[Bryce]

You should have told me before I sent you the parcel this week. Which just reminds me, I could have sent you that prototype too, if I had thought of it... Oops.

Bryce.

[TFM]

Get that prototype into the internet, and your will have great founding for new projects 

[Bryce]

It's the 16 Slot version, that used a different flash with a different page size. Although the hardware still works, it doesn't work with your software. We had one very early version, that worked with it, but we changed to the larger flash and the software only works with that now.

Bryce.

Edit: The flash is full of ROMs and can be written to with an EPROM programmer, so you could still use it as a ROMBoard I suppose.

[TFM]

It's the 16 Slot version, that used a different flash with a different page size. Although the hardware still works, it doesn't work with your software. We had one very early version, that worked with it, but we changed to the larger flash and the software only works with that now.

Bryce.

No problem, I developped it in Shaddow mode in the same time. You just need to check it once. IIRC the page size was only &80 bytes instead of &100 and sure, it had 256 KB. Have to look at the source at home... means later ;-)

[amstar]

Hi there! 
Does anybody know if it still possible to get a Megaflash?
Great forum by the way!  Thanks!