The DDI-2

[robcfg]

I hope plutonium got cheaper, otherwise the postage will be higher than sending it from UK... 

[Token]

Fantastic!


I have already two 6128, so what I really want is to use more my beloved 464 


It's hard to find a 464 memory expansion, it would be awesome to add it.
It has been reported that most games worked with the Dktronics 64k expansion.


I never bought the 6128 because it was a cheaper solution.
(I got two of them on ebay)
And the DD-1 is rare and often more expansive than a 6128 anyway.


Nowdays, having a 464 with DD-1+64K instead a 6128 is only meant to keep the original Amstrad, "464" with it's sooo british looking.   

[Badstarr]

Actually I have noticed something like this "timing" issue on my as yet unfinished GX4000 mod. It may or may not be the same thing, as the FDC interface is a copy of the Plus schematic. I can actually force the "press play and any key" error by loading and running the Batman forever demo, do a hard reset and then type "cat" or "run" etc and it either defaults to tape or it has read errors from the HxC. Turn the power off for five minutes and switch it back on everything is back to normal. Occasionally the error will show up every now and then and a reboot fixes it but it always goes weird after The BF demo.

[Bryce]

That's wierd. What does the BF demo does that could cause that?

Bryce.

[Devilmarkus]

Also CPC+ Emulators sometimes get bugged and show "Press play then any key" after a reset...
I dunno yet, why this happens...

[Badstarr]

My hypothesis was that the instances of the bug that did not involve the BF demo were possibly down to a pull down resister or two not asserting the correct configuration at start up, possibly the earth reference going funny or something, just a bit of a shot in the dark. Though if an emulator exhibits the same behaviour then I suppose it's just a firmware bug.

I'm not sure exactly why the BF demo that does it, I think its possibly associated with the HxC, I haven't tried a FDD with my GX4000 mod as yet and as it stands I haven't got a great deal of time to dedicate to the project for the time being. However, I tried the machine out many times with a few demos (more to sit back and enjoy my handiwork and watch the FDC I built do its stuff).  I noticed that when I power cycled the machine was in tape mode when it booted back up, so my initial reaction was that I should do some fault finding on my mods.

A few checks with the multimeter, confirmed all was fine so I connected everything back up and the machine was back in disk mode at boot. So I chalked it up to a dodgy connection, but I noticed the bug happened each time I ran the BF demo. Its usually the same 2 things that occur, either default to tape mode |DISC causes a reboot. Or the HxC returns read errors if the machine is in disc mode at boot. I can solve the issue by changing the disk image and power cycling or just powering down for a good few minutes. Everything works flawlessly until the next time I run the BF demo.

My theory was that the BF demo has left the the FDC in a state where the HxC still thinks it's talking to the machine and this is maybe causing some initialisation problems at startup, in other words the firmware finds junk on the FDC address and assumes that there is no FDC hardware installed. Or if it does manage to detect the FDC hardware the data lines are getting gibberish from the HxC causing the read errors.

I'm probably barking up the wrong tree... It's certainly an intriguing bug though!

[TFM]

Also CPC+ Emulators sometimes get bugged and show "Press play then any key" after a reset...
I dunno yet, why this happens...

Well, I saw that on real machines too. 

[karlmag]

Hi,

This is certainly an interesting project.
I would want at least one for sure. 

[Bryce]

Unfortunately I had to put this project on ice for a few months due to other priorities, but I will get back to it soon I hope.

Bryce.

[karlmag]

Unfortunately I had to put this project on ice for a few months due to other priorities, but I will get back to it soon I hope.

Bryce.

I can appreciate that. Life happens, etc.

While being an electronics wannabe, i.e probably not able to be of much practical help, I wonder if you would mind posting a high(er) resolution picture of the schematics of the circuit you have so far? The pics you did post comes up (at least for me) way too course to be able to really see or read anything at all off of them.

Thanks.

[Bryce]

Hi Karlmag,
     unfortunately not only life happens, shit happens too. And it's because of this that I have deliberately made the schematic unreadable. Although my projects have been open-source in the past, I have recently had some very negative experiences in this respect, so I have decided to keep my designs closed until they have been built, tested and are ready for release.

Thank you for your offer of support.

Bryce.

[karlmag]

Hi Karlmag,
     unfortunately not only life happens, shit happens too. And it's because of this that I have deliberately made the schematic unreadable. Although my projects have been open-source in the past, I have recently had some very negative experiences in this respect, so I have decided to keep my designs closed until they have been built, tested and are ready for release.

Thank you for your offer of support.

Bryce.

Hi Bryce,

Sorry to hear about your bad experiences. :-(
It does, however, explain the pics. And given that I also do understand why you do it the way you do (albeit I will admit to finding it a bit annoying too, though mostly due to me being a curious bastard ;-) ).
I hope you will find time to finish and release this project :-)

Have a great day!
--
Karl Magnus aka KarlMag

[Bryce]

The blurred picture isn't meant to annoy curious people It's more to show that this is actually being worked on and not just an idea / concept being talked about.

Bryce-

[Munchausen]

Any loaders that use direct fdc disc access will set the side.

AMSDOS also sets the side, but here we could hack it so we could force the side we wanted, but this would only work for loaders that use AMSDOS, and not direct to the fdc.

Resurrecting an old comment, but it seems it would still be useful to set the side in software as well as having a hardware switch. A 3 position switch - side A, side B, software controlled?

[Bryce]

That's the plan

Bryce.

[Munchausen]

Cool


Eagerly awaiting the DDI-2!

[the KING]

Bryce,
Sorry for opening a very old thread, but did you finish this project?


Tom

[Bryce]

No, due to lack of time, I passed the design on to others to finish. Piotr has released a DDI-1 clone in the meantime.

Bryce.

[ZbyniuR]

What is a difference between yours project and Zaxon's DDI clone?

I don't have 464, but I think on market still no exist something what can change 464 into 6128 in one piece of hardware.

I suppose that is enough for most of 464 owners, and they don't need more ROM and RAM. But of course they should say what they think about it.

[TFM]

     unfortunately not only life happens, shit happens too. And it's because of this that I have deliberately made the schematic unreadable. Although my projects have been open-source in the past, I have recently had some very negative experiences in this respect, so I have decided to keep my designs closed until they have been built, tested and are ready for release.

Very sadly that's true. In 1995 there was the ROM-RAM-Box, that is ... 20!!! years ago. Since that time there was no such expansion. Thanks to you Bryce after all the time the MegaFlash was there for us. And the MegaFlash served as core of an explosion of new hardware products. Some took the design into their own projects and in some cases even added new features. For example TotOs X-MEM contains RAM and ROM. And he produces that and provides that without making any money. That's a great service to the community. And the MegaFlash did enable all of that.
Now there is a dark side too, other people took (or shall I say steal?) the design an reproduced that (with or without permission - I don't know, but I can imaging) - just to cash in. An example is imho the so called MegaFlash EX and there is another one (I forgot it's naming).
So, yes, it all has two sides. And I can totally understand that people draw consequences. 

[Bryce]

The difference between my DDI and piotrs is that mine was based on the FDC9266 and not the µPD765 like the original CPC hardware. It also included an ABBA switch and Ready bridge if required and headers for both 34pin Shugart and 26pin CPC drives. It had a switchable AMSDOS/ParaDOS ROM7 on board, but this could be disabled in case you wanted to use a different DOS on a ROMBoard.

@TFM: Yes, when I joined the CPC community there was a complete lack of hardware development, in fact since DrZed left there seemed to be zero hardware being developed. The MegaROM, MegaFlash, LowerROM, Mouse Adapters and S-Video kicked things off and since then there has been a flood of great hardware being released. Just look at what's being done today: TotO, Piotr, Gerald, rpalmer etc (I hope I haven't forgot anyone) have come out with fantastic new hardware. Others such a Talrek keeping the supply alive. The CPC hardware scene has completely changed and this also motivates the software guys to release new stuff too. I hope I had at least a small influence on the situation.
Regarding MegaFlash clones. I never hid my designs or source code, it's all open source and free for anyone to use and expand. That's what open source is all about. Even (almost) exact clones like the MegaFlash NG from "your mate" and the Flashgordon (which I think you were referring to) are great pieces of hardware that support and expand the scene and I'm very happy that people liked my hardware enough to copy it - As Charles Caleb Colton said: Imitation is the greatest form of flattery. The only thing I don't like is people selling clones (or hardware) dirt cheap because this undermines the hardware scene. Hardware requires quite a bit of investment and risk in the development stages and should be included in the end price of the device. If users see hardware being sold for pennies, they expect everything to cost that little. This discourages the other hardware developers from working on new devices that may cost a substantial amount to develop.

Bryce.

[TFM]

Well, well spoken. 

However I disagree about pricing. CPC is not a real market, so people do things for fun, or because they can do it, or because a device is needed or or or... but imho not for money making.

Sure it's nice to get some appreciation for your work. But how can you argue again cheap pricing? I made the MegaFlash ROManager and I did not get a single Cent out of it. Same is true for that dodgy roman tool.    Are the hours of work we put in nothing worth?

See the dilemma: Following your argumentation you would be required to pay some money for every new program. If somebody would ask me if we want it all for free or all for money then I'm fine with all for free.

And nobody please tell me that hardware and software are different. You put time and money in both of them. 

[gerald]

And nobody please tell me that hardware and software are different. You put time and money in both of them. 

I tell you :  HW and SW are different.

While you mainly need time for SW development, you also need tools to do HW development.
There is no such free oscilloscope, logic analyser, PCB nor components. You have to pay for this.
Each prototype has a cost, and each iteration or rethink has a cost money wise.

Once the product is working, yes you can use someone's spare time to duplicate it at component cost.
But there is a limit to the money you can spend on developing without expecting a return.
There is also a limit to the fun factor of duplicating (ie making) your HW for everyone to enjoy it. There is no such download equivalent to HW 

And that's not a matter of market.

[TFM]

Agreed that there is no such download as hardware. And every piece needs some input, so of course it has its price. But this should be fair.

However for making software you need to invest quite a lot, there is no such thing like the original hardware to test, a good monitor for programming, the need to buy hardware addons to test software and also RAM an ROM expansions for more efficient coding.

Now don't tell me that I would have all this anyway, because you have all your oscilloscopes and so an anyway too. 

I totally understand that creating hardware means also to put some money in for development, PCBs, chips and 999 other things, but .. BUT ... you do sell it for money, so you get your costs back. While software is ... IS ... usually free. 

At the end the people can decide if they buy a product or not, but I still think it's AWESOME that some people also produce for 'dirtcheap' prices, because in this days not everybody can afford things. I know quite some genious people getting no job and having no money. So great for them to have a chance to realize a dream once in a while. 

[Bryce]

I totally understand that creating hardware means also to put some money in for development, PCBs, chips and 999 other things, but .. BUT ... you do sell it for money, so you get your costs back. While software is ... IS ... usually free. 

Of course hardware people will have the equipment (most of it) already, it's the prototypes etc that cost money and you only get your money back if you price your device correctly. If you spend a few hundred euros building prototypes to refine your product, then those costs should be in the final price. If someone then comes along and clones the device without having to do any development and sells it for half the price, you'll be told you were ripping people off and end up with further losses because people buy the clone and you are left with stock. Software "prototypes" cost time but not money, stock doesn't exist (except in cases where you sell physical copies), so the risk is minimal in comparison. I don't charge for my time, if I did, the hardware would be incredibly expensive, but if it cost me €500 in prototypes and trials I'll certainly add it to the final price.

Bryce.