Mother X4 and DDI3 - Mods

[LambdaMikel]

As discussed in a couple of other threads (thanks @Duke  and @Rennert and @revaldinho  ), in order to connect DDI3 and other edge connector-based hardware to the popular and useful Mother X4, bridge / jumper the diodes, and then either use a straight IDC box header or a female IDC connector.
The former is preferred for Mother X4 (increased stability); the latter also works, but is unstable (see pics).

[LambdaMikel]

PS The little PCB can be downloaded from here:
https://oshpark.com/shared_projects/3yA33GYO
Just cut it with a scroll saw or hex saw(thanks to @revaldinho  for that idea  )

[LambdaMikel]

PS2 Or use the LambdaBoard:
https://oshpark.com/shared_projects/fCGxBoNY

[LambdaMikel]

*end of whining*

[LambdaMikel]

In princple, the straight IDC Box Header-based solution is also shaky, but it is supported to some extent by the rear line of header pins sticking out of Mother X4, supporting the DDI3's edge connector.

After all, it works, but I consider these solution unsatisfactory and too shaky. So I'll keep using the LambdaBoard for edge connector-based hardware extensions.

If you have other / better solutions (not cable-based), let us hear please 

[LambdaMikel]

@Piotr if you should ever do a new batch, maybe also add a MX4-based DDI3 to your assortment
In principle I agree that edge connector should be used only for "retro" hardwaresuch as DDI1 and old DKtronics devices and so on.

[LambdaMikel]

Now, looking again at the Amsdap and whining about it in


http://www.cpcwiki.eu/forum/amstrad-cpc-hardware/amsdap-amstrad-msx-adapter-connecting-any-msx-io-hardware-to-the-cpc/

and its pysical layout and spatial slots arrangement, if you apply any of these methods above to add the DDI3, you will probably block some of its MX4 or MSX slots... So it seems that cable connection of DDI3 to Amsdap is the only way to go  Anyhow. I am done with this issue now.

[TotO]

This hack is dangerous. You can damage your CPC or the connected expansions if later you forgot and a PSU is plugged on the MotherX4.

Just sad that DDI-3 do not provide a passthrough connector (and a switch to disable the RAM for the last version).
I was using it for doing fast tests on my 464 and X-CPC and that is not practical at all. (but enough for a lambda user)

[LambdaMikel]

This hack is dangerous. You can damage your CPC or the connected expansions if later you forgot and a PSU is plugged on the MotherX4.

Right, since I don't use the external PSU, I should just desolder / remove it.

[LambdaMikel]

@TotO since we have you here in this thread, what's your recommendation then to get DDI3 running with Mother X4 ?

[LambdaMikel]

Just sad that DDI-3 do not provide a passthrough connector (and a switch to disable the RAM for the last version).

But remember, other important "retro" old hardware extensions - DDI1 - don't do that either... and now new boards are being proposed that hijack the CPC 464 edge connector and don't offer expansion port pass-through either...

[TotO]

When someone build new boards, it is the good occasion to fix the problem of the previous. (more when it is not the first try)
It is like the mouse adapter that orriginaly only support one button and nothing improved into a clone to suport two, etc.

By the was, about DDI-3 and MotherX4, if you do not use external PSU, yes what I will does is to remove the dioles and put a link only from the CPC pin 27 to power all the expansions. (supposing your CPC got enough power for that)

[LambdaMikel]

As already suggested, maybe @Piotr can make a new version with M4X connector.
It should certainly pay off for him - if you look on YouTube, then there are more videos about DDI3 than about any other recent CPC hardware add on. So I believe - with the exception of M4 and XMem - DDI3 is probably the most successful piece of new CPC hardware of the last 5 years. Congrats to @Piotr  for this.

[TotO]

I can't congrats as peoples asked for the passthrough feature since the DDI-2 release. (and no answer to my questions)
Last but not least, adding the floppy emulation and the RAM is not enough to make all the 6128 programs running, because the firmware and BASIC are not the good.


I have seen a newbie selling an edge adapter including a MX4 slot, but the price is just a joke.

[LambdaMikel]

I have seen a newbie selling an edge adapter including a MX4 slot, but the price is just a joke.

That person is probably me, thanks  (depending on the definition of newbie - I had my first CPC 464 in 1985    ) Or maybe there some other source for these connectors I dont know about     Anyhow - my PCB gerbers are online, so people can just make it themselves.
I only charge money for my time of assembling it. I am not making any money
with the products themselves, hence everything I am selling is shared on OshPark.


Further, in my offers Ebay and Sellmyretro, free shipping is included in the price, which is 14 $ from the US to Europe. 

[LambdaMikel]

I can't congrats as peoples asked for the passthrough feature since the DDI-2 release. (and no answer to my questions).

Seems there are also some more recent examples of this kind of stubbornness.   

[LambdaMikel]

I can't congrats as peoples asked for the passthrough feature since the DDI-2 release. (and no answer to my questions)

Well, I'd say let's not start another round of @Piotr  bashing, I like his work. And he has responsibly resolved all my issues I had with his hardware.

[Bryce]

When someone build new boards, it is the good occasion to fix the problem of the previous. (more when it is not the first try)
It is like the mouse adapter that orriginaly only support one button and nothing improved into a clone to suport two, etc.

By the was, about DDI-3 and MotherX4, if you do not use external PSU, yes what I will does is to remove the dioles and put a link only from the CPC pin 27 to power all the expansions. (supposing your CPC got enough power for that)

There was a mouse adapter that only supported one button?? How useless is that? Even the original AMX mouse had 3 buttons, which is why my adapter supported all three from the start. Otherwise none of the art packages would have worked.


Bryce.

[LambdaMikel]

There was a mouse adapter that only supported one button?? How useless is that?

There is also that thing called the Macintosh computer which also only ever had one - and it was sold as a feature. Don't confuse the user with too many buttons....  

[Bryce]

Oh I thought he was talking about some sort of CPC mouse adapter.

Bryce.

[Piotr]

Hmm, sorry , is not my fault. DDI 3 was designed as single interface for plug and play direct to 464.  Not as "add on"  for MX4 board what made only problems with stability. Long wires, poor power supply, weak connectors and many others problems. Btw, i made DDI3 with via thru connector too.

[LambdaMikel]

DDI3 works perfectly fine after Mother X4 mod above.

Best option for Mother X4 though is indeed with an extra PCB and cable; the other 2 solutions shown above are more shakey and less reliable it seems.  Since I am not a big fan of even more cables, I will just stick with LambdaBoard for this use case, but I am glad that Mother X4 also works with DDI3 in principle after the mod.

[LambdaMikel]

... just to complete the list of options, option number 4 - LambdaBoard.

[LambdaMikel]

... and for complete completeness of this thread, @revaldinho solution to this problem
( @rpalmer solution doesn't count, he does not have an edge connector and he is hence disqualified from this competition  )

[TotO]

Oh I thought he was talking about some sort of CPC mouse adapter.

You understood well. I was takling about a CPC mouse adapter.
I have made some search, and it was the DK-Tronics clone done by Talrek. The original has 1 button, and the clone not fix that.
It's only 2 wires to add on the design as there is a free input and output to the embedded IC for that.