MegaFlash Progress

[TFM]

Love the Ding sound. Great job!!!!

One small suggestion: can you draw a window for the file list on the right? It doesn't look too good right now...

You can use a comfortable file-selector when using the version for FutureOS.

[TFM]

Great work Bryce and TFM, looks really good.


Btw Bryce, you need a copy of my patched cartridge - no annoying f1/f2 menu and you can still access Burnin' Rubber if you really want to by RSX 

Thanks! For the Cart did you use the patched Incron Amsdos ROM? Or did you use another way? I'm just curious.

On my Plus I have (currently) the old ROM-RAM-Box with the Inicron-Patched-Amdsos. So it's the old Amsdos, fulliy compatible, but pachted to NOT-crash with the Plus, also the F1-F2 Menue is missing. I always thought it would be good to integrate that one in the Cart itself.

[redbox]

Thanks! For the Cart did you use the patched Incron Amsdos ROM? Or did you use another way? I'm just curious.

I did try to patch the Amsdos ROM at first, but then found that the OS ROM actually called the menu in the Amsdos ROM.  Therefore, I patched the OS ROM to start Basic instead and because the Plus Amsdos ROM has RSXs for Burnin' Rubber (|GAME, |JEUX, |SPIEL or |JUEGO) it didn't need to be altered in any way. 


I know you can get rid of the menu by replacing Amsdos with for example Parados, but this means you can't access the Burnin' Rubber game anymore because the RSXs in the Plus Amsdos are lost.

On my Plus I have (currently) the old ROM-RAM-Box with the Inicron-Patched-Amdsos. So it's the old Amsdos, fulliy compatible, but pachted to NOT-crash with the Plus, also the F1-F2 Menue is missing. I always thought it would be good to integrate that one in the Cart itself.

I didn't realise the Plus version of Amsdos had any compatibility problems.  What causes it to crash?

[TFM]

I didn't realise the Plus version of Amsdos had any compatibility problems.  What causes it to crash?

Yes, some software is not running with the Plus Amsdos (0.70), because it's made for the CPC oG Amdos (0.50) and jumps directly into the ROM. Especially some games have the problem. If the Plus has the old Amsdos you can't start Burnin Rubber again, but more old games will run. Therefore it's an advantage to have it on a ROM that can be switched on or off.

If you just replace the Amsdos 0.7 in the Cartridge with the old Amsdos 0.5 then the system will crash. This happens due to the fact that the OS jumps in the Amsdos at power on - but you mentioned this before. And if you have patched the OS to NOT-jump into Amsdos it shouldn't be a problem at all.

I can't tell about ParaDOS, since I never use it. It's for sure a great DOS, but I have all my soft on Vortex format and so I use XD-DOS which has a nice set of RSX commands and supports Vortex-Format too (so I don't have to use VDOS). Just for curiosity: In Germany we worked for a decade with XD-DOS, Parados didn't leave the island for a long time. So the old sceners all use Vortex format - and this is not at all supported by Parados. So, just bad luck, but no offense.

[redbox]

Yes, some software is not running with the Plus Amsdos (0.70), because it's made for the CPC oG Amdos (0.50) and jumps directly into the ROM. Especially some games have the problem. If the Plus has the old Amsdos you can't start Burnin Rubber again, but more old games will run. Therefore it's an advantage to have it on a ROM that can be switched on or off.

Didn't know this and thanks for the explanation.

If you just replace the Amsdos 0.7 in the Cartridge with the old Amsdos 0.5 then the system will crash. This happens due to the fact that the OS jumps in the Amsdos at power on - but you mentioned this before. And if you have patched the OS to NOT-jump into Amsdos it shouldn't be a problem at all.

Yes and I think it's pure luck that a non-patched Plus OS doesn't crash the Parados ROM (unless the author was very clever and took the Plus into consideration when programming it).


I can build you an image that contains the patched Plus OS and Amsdos 0.5 if you want as this would work?

[TFM]

Yes and I think it's pure luck that a non-patched Plus OS doesn't crash the Parados ROM (unless the author was very clever and took the Plus into consideration when programming it).

Hehehe! I LIKE the way you think 

[Bryce]

Because I asked him to.

Bryce.

Edit: Mainly because of the name: The Device is called MegaFlash, not MegaFlashROM, and I didn't want it to be documented under the wrong name.

[Executioner]

My understanding is the same.

The ACID talks to the ASIC. If the conversion is not correct, the z80 is forced to read bad data and it will then crash.

How did you come to that conclusion? I just assumed (possibly incorrectly) from all the documentation that the data available to Plus from the cartridge port had to be encrypted by the ACID (not the ROM itself) before being presented to the Plus on the other side of the cartridge connection which then decrypted that data with it's own internal un-ACID (probably internal to the ASIC).

I think the idea is that a cartridge *MUST* be inserted for the plus to run, but only because the cartridge also contains the acid.
The ROM data is not encrypted as we know.

If you inserted a tiny board with just an ASIC on it into the cartridge slot, the plus will boot. It will then read "floating bus" unless some roms assert themselves.  So then the roms need to be provided externally (rom board to provide 0-15, other to provide OS)

Has anyone ever made a tiny board with just an ACID to test this either? Is there a ROM board that will provide a lower ROM?

[OCT]

some software is not running with the Plus Amsdos (0.70), because it's made for the CPC oG Amdos (0.50) and jumps directly into the ROM. Especially some games have the problem. If the Plus has the old Amsdos you can't start Burnin Rubber again, but more old games will run. Therefore it's an advantage to have it on a ROM that can be switched on or off.

If you just replace the Amsdos 0.7 in the Cartridge with the old Amsdos 0.5 then the system will crash. This happens due to the fact that the OS jumps in the Amsdos at power on - but you mentioned this before. And if you have patched the OS to NOT-jump into Amsdos it shouldn't be a problem at all.

I can't tell about ParaDOS, since I never use it. It's for sure a great DOS, but I have all my soft on Vortex format and so I use XD-DOS which has a nice set of RSX commands and supports Vortex-Format too (so I don't have to use VDOS). Just for curiosity: In Germany we worked for a decade with XD-DOS, Parados didn't leave the island for a long time. So the old sceners all use Vortex format - and this is not at all supported by Parados. So, just bad luck

The lucky affluent ones who could afford Vortex/Dobbertin back in the day, that is.
Hence the idea to have, say, two (rather than single) bits of DIP switch ("Mäuseklavier" pour les initiés ) to get 3+1 choices (the latter on the cartridge and 3 on the MegaFlash) for each of ROMs 0 and 7 (as few low-level applications will bother looking anywhere else), allowing for perfect compatibility from having all flavors of OS and DOS available (at their standard ROM numbers) on one machine.
Yes, it would require some minimal circuitry/logic to have each of these appear at the standard ROM numbers, but the only alternative would be hard-hacking a cartridge for the Plus, or piggy-backing ROMs on the old-gen CPCs.
Presumably only very few people (if anyone) would miss the "opportunity" to have more than 28 ROMs installed at once (when dedicating 2 more slots to each 0 and 7), but the benefits of switchable (D)OSes would be felt by anyone ever encountering old software (unsurprisingly on a CPC ).

While a little tricky to put the concept into words, it will be quite intuitive to use.

BTW, do make this an option on the forthcoming Symbiface3 too (this is a blatant, blunt attempt to summon it back onto its road to release before Bryce and rpalmer have to re-invent its each and every feature ).

[Bryce]

@Executioner: The ACID definitely doesn't encrypt any data, it reads a few bits, makes a calculation and sets a single control signal to 0 or 1 depending on the outcome. The data lines of the cartridge ROM are parallel to the ACID, they don't go through it, so they are directly connected to the data bus.

@OCT: Thanks for the idea, but the MegaFlash hardware is now final, no further changes, so you'll have to wait for the SF3 and hope that Dr. Zed has incorporated this.

Bryce.

[arnoldemu]

How did you come to that conclusion? I just assumed (possibly incorrectly) from all the documentation that the data available to Plus from the cartridge port had to be encrypted by the ACID (not the ROM itself) before being presented to the Plus on the other side of the cartridge connection which then decrypted that data with it's own internal un-ACID (probably internal to the ASIC).

I dumped some carts using an Amiga a few years ago. I set the ACID to inactive (some lines to 0v some to 5v). I read the data without breaking the cart and non of it was encrypted.

some info is on my website.

Also, testing by mcleod_ideafix (when investigating an acid replacement) showed that without the acid the z80 reads bad data, it seems to be floating bus. The ASIC doesn't get an answer, so tells the z80 to read the wrong thing.

The value is 0x079 or so which is the same from doing an IN to an unmapped port on Plus.

Has anyone ever made a tiny board with just an ACID to test this either? Is there a ROM board that will provide a lower ROM?

Yes, Amstrad did it in their demonstrator hardware (The csd).
I think.

Or the acid may be moved onto the daughter board.

[Bryce]

There were two devices that could replace the lower ROM:

ACUs ROM Changer:
http://www.cpcwiki.eu/index.php/ACU_Romchanger

And FO DOS:
http://www.cpcwiki.eu/index.php/FO-DOS

As far as "only ACID" in cartridge is concerned: I have a small project that puts the ACID inside the CPC so that cartridges don't need to have one, but I never released this project. If anyones interested, I can dig out the info and put it on the Wiki.

Anyone who has converted a cartridge to Socket (for swapping ROMs) can also do the "ACID only" test.

Bryce.

[arnoldemu]

As far as "only ACID" in cartridge is concerned: I have a small project that puts the ACID inside the CPC so that cartridges don't need to have one, but I never released this project. If anyones interested, I can dig out the info and put it on the Wiki.

I would like to see this in the wiki for completeness.

[Bryce]

No problem, I'll dig it out and document it when I have time.

Bryce.

[OCT]

@OCT: Thanks for the idea, but the MegaFlash hardware is now final, no further changes, so you'll have to wait for the SF3 and hope that Dr. Zed has incorporated this.

Could be a looong wait if that thread is any guide. And longer yet to get replies from Prodatron...

Without tons of bells and whistles actual or announced, yours has the advantage of being available. 

[TFM]

@OCT: I undestand your POV. And it's a good thing to have ideas, and to share them. On the other hand it makes it dangerous, beause the good thing about a final design is, that the product will be available. On the other hand if you incorporate a couple of good ideas more, then the design must be changed again and again. So the release would take place rather in years than now.

IMHO it's a good thing to finish something and release it. It's just a good feeling to be able to do something for the community.

On the other hand it would also make sense to think about future projects and expansion cards with multiple functions. However to create such a beast is very, very time consuming. Before we can start dreaming we must check if such a project would be realistic.

There is another point I want to mention, even if I'm getting a bit offtopic now. When creating new hardware it _IS_ a very important point to be compatible to existing expansions. Bryce did show with a variety of expansions that this is doable. Why? Well, if you don't stay compatible, then we will end up with 10 kinds of cards to perform function XY and every kind of card will be owned by three people and it will just be chaos. (For example I do know six working hard-disc controllers for the CPC!).

So whatever we intend to plan for the future, let's try to stay compatible with existing expansions which perform similar functions. In addition we will already HAVE software dealing with it.

[rpalmer]

in response to TFM/FS about compatibility,

I agree that its always best to agree on some standards for hardware connected to the CPC, but it is also difficult to get to a standard since there are so few free I/O ports to work with and that with so many devices that have been developed there is going to be the inevitable collision of devices using the same I/O port.

In an ideal situation the software should not be hardware coded for specific I/O ports. This makes the software really fixed to one device and could make the whole project less than desirable against similar hardware.

The only software I know of which has this built into its design is of course the HDOS ROM (that I have developed and released) which relies on device drivers controlling the additional hardware (such as IDE/8255, SymbiFace, Yarek IDE, etc).  The HDOS system has only the standard floppy and RAM disk drivers.

I plan to implement the same philosophy in the development of the CPC-Ethernet card.  I have already created a draft of the drivers for the hardware and the driver handling for HDOS allows for the management of the routines to be available to external software, such as TCP/IP in ROM or any other custom software.

It would be nice if the megaflash, IDE/8255 and ethernet card combo (including all software) were connected up on one machine to really show off what the CPC could do!

rpalmer

[Bryce]

With ROMBoards (including the MegaROM and MegaFlash), it's quite easy, because there aren't different addresses you can use. The address HAS to always be the same, otherwise it just won't work. The only problem that occurs is when the ROMBoard doesn't fully decode the address bus and answers to several addresses or several ROM Numbers for a single ROM. The MegaROM and MegaFlash don't have this problem, but some of the old ROMBoards (both DIY and commercial) had this problem.

Bryce.

[rpalmer]

indeed you are correct bryce, that some devices only partially decode the I/O address and this quite evident when you look at how the standard I/O ports on all CPCs use a specific address line for an I/O port.

rpalmer

[TFM]

In an ideal situation the software should not be hardware coded for specific I/O ports. This makes the software really fixed to one device and could make the whole project less than desirable against similar hardware.

Well, I agree a lot with you :-) But not in this point. Software specially written for one hardware is way more superior to genetic drivers or drivers at all. It's not only more quick, it's also more reliable and stable. As example FutureOS may serve, which provides very quick functions for a lot of hardware.
The downside of it is, that you always have to redo your software for every new piece of hardware. But rather I have more work, then having not the most efficient routines. I just like the challenge :-)

[Executioner]

There were two devices that could replace the lower ROM:

ACUs ROM Changer:
http://www.cpcwiki.eu/index.php/ACU_Romchanger

And FO DOS:
http://www.cpcwiki.eu/index.php/FO-DOS

As far as "only ACID" in cartridge is concerned: I have a small project that puts the ACID inside the CPC so that cartridges don't need to have one, but I never released this project. If anyones interested, I can dig out the info and put it on the Wiki.

Interesting. Do these work on a Plus? All Plus catridges have an ACID inside them, so if you could simply change the lower ROM (and upper) in a ROM board, you could boot into the OS with any game cartridge in the cartridge port so long as it had an ACID in the cartridge.

Do we already have non-destructive ways to dump cartridges? Are there any cartridges left to dump (that we can get hold of), and what ever happened to Chase HQ 2?

[Bryce]

Amstrad managed to keep the expansion port on the Plus compatible with the Classic CPC, although the hardware behind the port is very different, so technically they should work on a plus too.

Cartridges can be easily dumped in a non-destructive way, but all known cartridges have already been dumped and the images are readily available online. Except for the elusive CHQ2, which still holds the coveted status of "Myth?".

Bryce.

[arnoldemu]

Interesting. Do these work on a Plus? All Plus catridges have an ACID inside them, so if you could simply change the lower ROM (and upper) in a ROM board, you could boot into the OS with any game cartridge in the cartridge port so long as it had an ACID in the cartridge.

Yes I think that should work.

Do we already have non-destructive ways to dump cartridges? Are there any cartridges left to dump (that we can get hold of), and what ever happened to Chase HQ 2?

I will dig out my amiga files. My original hardware was made for the amiga a1200.
The software was written in 68000, and the reader was wire-wrapped. It had 2 x 12-bit ripple counters. It took time to make

[TFM]

Did you find it?

[dcdrac]

Does this help?

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