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General Category => Amstrad CPC hardware => Topic started by: LambdaMikel on 09:07, 08 June 18

Title: MotherX4 Alternative for CPC 464 Users
Post by: LambdaMikel on 09:07, 08 June 18
Out of "frustration" that my DDI3 cannot be easily connected to the Mother X4 (as it has no edge connector, and with a cable the voltage drop is too high for the DDI3 to work), I have designed an alternative. I'll make the Gerbers available if it works.

Title: Re: MotherX4 Alternative for CPC 464 Users
Post by: rpalmer on 12:03, 08 June 18
lambdamikal,

I already have a version of the MX4 available (see attached)

Rpalmer
Title: Re: MotherX4 Alternative for CPC 464 Users
Post by: LambdaMikel on 16:04, 08 June 18
lambdamikal,

I already have a version of the MX4 available (see attached)

Rpalmer
That's nice.
And it has an edge connector for my DDI3 at the end?
If so, where can I download the Gerbers.
Title: Re: MotherX4 Alternative for CPC 464 Users
Post by: rpalmer on 23:36, 08 June 18
lambdamikel,

There are no edge connectors, but an adapter can be used to connect it to the IDC socket to allow for original peripherals.

rpalmer
Title: Re: MotherX4 Alternative for CPC 464 Users
Post by: LambdaMikel on 23:48, 08 June 18
lambdamikel,

There are no edge connectors, but an adapter can be used to connect it to the IDC socket to allow for original peripherals.

rpalmer


Palmer,


see, this is exactly what I wish to avoid with that.


I have a solution with cables and adapters (a couple of my CPC Connectors plugged together and cables) that works for DDI3, but it is ugly and not very reliable. And, if paired with MotherX4, results in a voltage drop which renders the DDI3 non functional.


Hence this board.
Title: Re: MotherX4 Alternative for CPC 464 Users
Post by: LambdaMikel on 23:53, 08 June 18
lambdamikel,

There are no edge connectors, but an adapter can be used to connect it to the IDC socket to allow for original peripherals.

rpalmer


Also, not sure what you mean with original peripherals.
No matter what, you need an edge connector if you wish to use an original CPC 464 hardware extension such as the DKtronics speech synth or the DDI3. Where do I get an edge connector from otherwise.
Title: Re: MotherX4 Alternative for CPC 464 Users
Post by: revaldinho on 18:54, 09 June 18
I had the same problem - 464 and DDI-3 but wanting to use other cards too - but I solved it in a different way.


I took one of your own adapters, hacksawed off the edge connector and mounted it vertically on the back of the DDI3 using one set of connector holes. I put a 50W box header in the other set. So now I have the DDI3 directly plugged into the CPC464 and an expansion card connected at the back.


The snaps are a lot clearer than my description  :D

Title: Re: MotherX4 Alternative for CPC 464 Users
Post by: LambdaMikel on 20:02, 09 June 18
I took one of your own adapters, hacksawed off the edge connector and mounted it vertically on the back of the DDI3 using one set of connector holes. I put a 50W box header in the other set. So now I have the DDI3 directly plugged into the CPC464 and an expansion card connected at the back.
Good idea and very creative unintended use of the adapter!  ;D
I don't want to modify my DDI3 for this though. 
Glad it works for you!

With the new LambdaBoard, the DDI3 will be at the far end, and a single cable from the CPC 464 edge connector will go into the board. That should also increase physical stability since the DDI3 is quite heavy. And the edge can also be used to connect the DDI and DKtronics and the like at the end then without putting stress on the CPC motherboard's edge.
Title: Re: MotherX4 Alternative for CPC 464 Users
Post by: rpalmer on 01:38, 10 June 18
I have a solution with cables and adapters (a couple of my CPC Connectors plugged together and cables) that works for DDI3, but it is ugly and not very reliable. And, if paired with MotherX4, results in a voltage drop which renders the DDI3 non functional.

Don't forget the Right Angle board also allows for an independent 5V supply as well, so that should mitigate power supply issues to expansion cards.

rpalmer
Title: Re: MotherX4 Alternative for CPC 464 Users
Post by: LambdaMikel on 05:16, 10 June 18
Don't forget the Right Angle board also allows for an independent 5V supply as well, so that should mitigate power supply issues to expansion cards.
MotherX4 also has one, and I am not using it to avoid cable clutter. Someone suggested that one of the reasons for the voltage drop
might be the diode on the MotherX4. It should not be necessary to have an external additional PSU for a DDI3 and 2 or 3 more cards.
So, hopefully, the LambdaBoard will just work fine like that.
Title: Re: MotherX4 Alternative for CPC 464 Users
Post by: rpalmer on 23:47, 10 June 18
lambdamikel,

There is one other aspect to power supply issue and that is that the CPC was probably not mean't to have many expansions all drawing on the same 5V.

I mean just adding the DDI3 in some respects may be enough to drop the voltage to a point where other expansions may cause problems (and the same could be from other expansions).

There is also the age of the machine which maybe a factor in all of this.

The simple act of adding a bus extension card should not in theory cause any issues.

rpalmer
Title: Re: MotherX4 Alternative for CPC 464 Users
Post by: LambdaMikel on 00:26, 11 June 18
Palmer.

I believe that is a design flaw in the MotherX4. I don't have these voltage drop issues with the same PSU and CPC 464 if I connect a couple of my CPC connectors together with cables (ugly, but works). I will see how well it works with the DDI3 when the PCB arrives (next weekend). 
Title: Re: MotherX4 Alternative for CPC 464 Users
Post by: Duke on 07:03, 11 June 18
On MotherX4, you could add a simple switch to bypass the diode, to avoid the voltage drop (of course don't feed the ext. power, when bypassing the diode coming from the CPC VCC line).
Title: Re: MotherX4 Alternative for CPC 464 Users
Post by: LambdaMikel on 14:04, 11 June 18
On MotherX4, you could add a simple switch to bypass the diode, to avoid the voltage drop (of course don't feed the ext. power, when bypassing the diode coming from the CPC VCC line).
Right, I heard somebody has done that successfully. But even with that mod in place, I still want an edge for the DDI3's edge connector at the end such that I only need one cable in that setup. The less cables and connectors, the better from a reliability and voltage drop point of view  ;)
Title: Re: MotherX4 Alternative for CPC 464 Users
Post by: Duke on 15:42, 11 June 18
The less cables and connectors, the better from a reliability and voltage drop point of view  ;)
I agree - I would crank up your VCC and GND lines, as you have plenty of space. I think with the 7-8 mil tracks you can draw about 800 mA on 1 oz copper, it's probably fine, but just for the sake of it :)
Title: Re: MotherX4 Alternative for CPC 464 Users
Post by: Bryce on 16:14, 11 June 18
A bit off topic, but for those of you who are designing PCB routing/layouts, there's a great free program from SaturnPCB that will help you calculate PCB traces for current, voltage, stand-off etc, which every PCB designer should have on their PC:
http://www.saturnpcb.com/pcb_toolkit.htm (http://www.saturnpcb.com/pcb_toolkit.htm)
Many aspects of it aren't required for retro computing (there's a lot of high-frequency calculators), but the basics still apply.

Bryce.
 
Title: Re: MotherX4 Alternative for CPC 464 Users
Post by: LambdaMikel on 19:31, 19 June 18
I agree - I would crank up your VCC and GND lines, as you have plenty of space. I think with the 7-8 mil tracks you can draw about 800 mA on 1 oz copper, it's probably fine, but just for the sake of it :)

Yes, that might be a good idea... However, here is a question. In my understanding, the effective width of a track is determined by its narrowest part / segment, and that is already determined by the connector pin as well as the leads within the CPC going to the edge connector. How can a thicker / wider track make any difference if the narrowest part is before that segment? Also, the connector pin will have poor conductivity as well.

So, I think there are certainly good design patterns and best practices, including
- backside copper GND plane
- decoupling capacitors for each chip
- large width of tracks etc.
but I doubt that these are really strictly necessary for the current, voltage and frequency ranges the CPC operates at. Just my 2 cents  ;)  I am probably wrong though.
Title: Re: MotherX4 Alternative for CPC 464 Users
Post by: Duke on 19:50, 19 June 18
The CPC mainboard has huge power and gnd traces, like 30 mil or more, but otherwise I agree that it wouldn't make sense to beef them up if the former had smaller width. Just isn't the case.
And we already know what poor connectivity for the edge connector means (==trouble), so thats why it's essential to clean up the edge connector for proper operation.
Maybe it isn't a problem to power 4 devices with a 7.5 mil, 1 oz track , but it certainly could be and when you have plenty of space, I see no reason not to do it :)

Yes, that might be a good idea... However, here is a question. In my understanding, the effective width of a track is determined by its narrowest part / segment, and that is already determined by the connector pin as well as the leads within the CPC going to the edge connector. How can a thicker / wider track make any difference if the narrowest part is before that segment? Also, the connector pin will have poor conductivity as well.

So, I think there are certainly good design patterns and best practices, including
- backside copper GND plane
- decoupling capacitors for each chip
- large width of tracks etc.
but I doubt that these are really strictly necessary for the current, voltage and frequency ranges the CPC operates at. Just my 2 cents  ;)  I am probably wrong though.
Title: Re: MotherX4 Alternative for CPC 464 Users
Post by: LambdaMikel on 06:11, 20 June 18
The CPC mainboard has huge power and gnd traces, like 30 mil or more, but otherwise I agree that it wouldn't make sense to beef them up if the former had smaller width. Just isn't the case.
I could have sworn that I saw some skinny traces there, but I looked at the 464 board again, and you are right, they are indeed quite thick!  :) I changed to 15.75 mils (0.4 mm) - double the width I had previously, and not only for GND and VCC, but for all. I think that should really be sufficient now.
Title: Re: MotherX4 Alternative for CPC 464 Users
Post by: Bryce on 09:32, 20 June 18
Yes, that might be a good idea... However, here is a question. In my understanding, the effective width of a track is determined by its narrowest part / segment, and that is already determined by the connector pin as well as the leads within the CPC going to the edge connector. How can a thicker / wider track make any difference if the narrowest part is before that segment? Also, the connector pin will have poor conductivity as well.
Almost correct: The length of the thinnest part of track is also part of the equation. Also remember, that the volume of the conductor is also important, so the pins may be narrow, but they are much thinker and have more copper volume. Check out the "conductor Properties" tag in the Saturn PCB Toolkit software I recommended lately.

Not important in this case, but the frequency of the signal is also an important part of the equation.

Bryce.
Title: Re: MotherX4 Alternative for CPC 464 Users
Post by: LambdaMikel on 07:30, 22 June 18
The first version (thin tracks) is back. No problems so far  :)
Title: Re: MotherX4 Alternative for CPC 464 Users
Post by: Bryce on 09:25, 22 June 18
There's more electronics outside your CPC than in it! :D

Bryce.
Title: Re: MotherX4 Alternative for CPC 464 Users
Post by: LambdaMikel on 17:47, 22 June 18
There's more electronics outside your CPC than in it! :D
Happens with my Amiga 500, too - same rights for all retro computers please  :laugh:
Title: Re: MotherX4 Alternative for CPC 464 Users
Post by: LambdaMikel on 17:55, 22 June 18
Happens with my Amiga 500, too - same rights for all retro computers please  :laugh:
In case somebody has too much money:

https://www.sellmyretro.com/offer/details/lambdaboard-expander-32272 (https://www.sellmyretro.com/offer/details/lambdaboard-expander-32272)
Title: Re: MotherX4 Alternative for CPC 464 Users
Post by: LambdaMikel on 23:10, 03 July 18
I'll make the Gerbers available if it works.


As promised, for those who want to build it themselves:
https://oshpark.com/shared_projects/fCGxBoNY (https://oshpark.com/shared_projects/fCGxBoNY)
Take advantage of my CPC community assembly service otherwise  ;)
Title: Re: MotherX4 Alternative for CPC 464 Users
Post by: TotO on 17:40, 25 October 19
I was able to see your MotherX4 clone boards (4 and 1 connectors) and I'm surprise about the lack of +5V large track and ground plane to power the expansions. Instead, they use the same thin tracks than other signals... Really weak. Hope for users that was fixed since?
Title: Re: MotherX4 Alternative for CPC 464 Users
Post by: LambdaMikel on 17:49, 25 October 19
I was able to see your MotherX4 clone boards (4 and 1 connectors) and I'm surprise about the lack of +5V large track and ground plane to power the expansions. Instead, they use the same thin tracks than other signals... Really weak. Hope for users that was fixed since?
Nobody ever reported any problem with it - I believe that is because I do not have a voltage dropping diode on board  ;) 8) ;D So the voltage comes out ~ 4.8 V for most cards in the end if you have a reasonable CPC power supply.

External PSU "extra" expansion board PSU should not be necessary at all. Unlike other backplanes I can power the DDI3 without any extra PSU or board modification.

It's actually not at all a MotherX4 clone... that design was inspired by the old "Dat Becker CPC Hardware Erweiterungen" book - see page 80 / 87 here

http://www.cpcwiki.eu/imgs/4/40/CPC_Hardware-Erweiterungen.pdf (http://www.cpcwiki.eu/imgs/4/40/CPC_Hardware-Erweiterungen.pdf)
I guess you guys didn't have that in France and needed to "reinvent" it  :D


But yes, I have made a 2nd revision with wider tracks. I am not sure which one you have.

 
Title: Re: MotherX4 Alternative for CPC 464 Users
Post by: TotO on 17:51, 25 October 19
Nobody ever reported any problem with it - I believe that is because I do not have a voltage dropping diode on board  ;) 8) ;D So the voltage comes out ~ 4.8 V for most cards in the end if you have a reasonable CPC power supply.
Poor design and stupid answer to justify it... Think to users...  :picard2:


Title: Re: MotherX4 Alternative for CPC 464 Users
Post by: LambdaMikel on 17:55, 25 October 19
Poor design and stupid answer to justify it... Think to users...  :picard2:
Well you should only put things on board that are needed... not extra crap. IMHO.

Please read the whole answer first.
Title: Re: MotherX4 Alternative for CPC 464 Users
Post by: TotO on 18:03, 25 October 19
Well you should only put things on board that are needed... not extra crap. IMHO.
Your board use really too thin tracks for VCC and GND. I report that, because it is weak compared to the CPC mainboard design and using many expansions can cause problems to users. Here the problem.

So, please, don't change the subject about the original MotherX4 board design, because it is more clever than your clone craps.
:-\
Title: Re: MotherX4 Alternative for CPC 464 Users
Post by: LambdaMikel on 18:47, 25 October 19

Your board use really too thin tracks for VCC and GND. I report that, because it is weak compared to the CPC mainboard design and using many expansions can cause problems to users. Here the problem.

So, please, don't change the subject about the original MotherX4 board design, because it is more clever than your clone craps.  :-\

OK, you win  ;)

To base this discussion a little bit more on evidence, I can measure and post the voltages at the end of the different CPC backplane (including crap) solutions we have, with and without load (2 or 3 cards being plugged in I mean).

The reason and rationale for LambdaBoard was NOT to create a "crap clone of MotherX4", but to have an edge connector at the end.

And, as stated before, it is more a "clone" of this 80s book CPC backplane extension if anything, see Page 80 / Page 86:

http://www.cpcwiki.eu/imgs/4/40/CPC_Hardware-Erweiterungen.pdf (http://www.cpcwiki.eu/imgs/4/40/CPC_Hardware-Erweiterungen.pdf)


Anyhow. If anybody has a problem with it, please return it to me or grab the open source design of the LambdaBoard and improve it to fit your needs.

Have a good weekend.

Title: Re: MotherX4 Alternative for CPC 464 Users
Post by: TotO on 19:39, 25 October 19
Page 81 of the linked book, the tracks are at less two times wider than yours. Look the GND rails width on both sides!  :o

It is your design, I will not fix it because you put open source to not have to deal with problems. Think noob users, you are not Piotr and I'm sure that you will give a nice support if peoples encounter issues. The goal was just to know if the design was updated since (error is human).
Title: Re: MotherX4 Alternative for CPC 464 Users
Post by: LambdaMikel on 19:49, 25 October 19
OK, appreciate the input, but 3 more thingsI can rework the design at some point. But I would really prefer to only do that if somebody has an issue with it, so it would be based on some need... so far I don't see the need for that. But I will do what you suggested at some point. Thanks for the input! But mainly because I don't want to be perceived as beging stubborn, not because I see a need for that. I just dislike dogmatic doctrines "you have to do this or that" when there is not a lot of evidence in support for that.

Another thing that would be useful is to add the key lock gap, as suggested before, but a lot of work to cut it out manually. Not sure the PCB manufacturer will be able to do this.

Quote
It is your design, I will not fix it because you put open source to not have to deal with problems.


Hmm, not so sure that this was my intent when I put it open source... anyhow.


As always, it is a balancing act to find a good compromise between GOOD ENOUGH and OVER ENGINEERED design. And a design is never finished - there will be more iterations to come. :)
Title: Re: MotherX4 Alternative for CPC 464 Users
Post by: TotO on 20:12, 25 October 19
Hmm, not so sure that this was my intent when I put it open source... anyhow.
I'm sure, but it is sadly a recurent answer when someone ask for an update to a wiki or open source project -> DIY.

Here an alternative design based on the first version of the board (CTC-AY) : MotherX4_V2.1.zip (http://www.cpcwiki.eu/forum/amstrad-cpc-hardware/motherx4-alternative-for-cpc-464-users/?action=dlattach;attach=29820)


(http://www.cpcwiki.eu/forum/amstrad-cpc-hardware/motherx4-alternative-for-cpc-464-users/?action=dlattach;attach=29821;image)
Title: Re: MotherX4 Alternative for CPC 464 Users
Post by: LambdaMikel on 20:16, 25 October 19
I'm sure, but it is sadly a recurent answer when someone ask for an update to a wiki or open source project -> DIY.

Here an alternative design based on the first version of the board (CTC-AY) : MotherX4_V2.1.zip (http://www.cpcwiki.eu/forum/amstrad-cpc-hardware/motherx4-alternative-for-cpc-464-users/?action=dlattach;attach=29820)


Thats great - now, if I ask you to PLEASE ADD AN EDGE CONNECTOR to it, will you do it? Ore are you asking me to DIY  ;)
Title: Re: MotherX4 Alternative for CPC 464 Users
Post by: TotO on 20:19, 25 October 19
Thats great - now, if I ask you to PLEASE ADD AN EDGE CONNECTOR to it, will you do it? Ore are you asking me to DIY  ;)
There is already an edge adapter to plug on the passthrough pins, to be at the right height for the original interfaces.  ;)
Title: Re: MotherX4 Alternative for CPC 464 Users
Post by: LambdaMikel on 20:21, 25 October 19
There is already an edge adapter to plug on the passthrough pins, to be at the right height for the original interfaces.  ;)


And would it not be better to have that directly on the PCB, such that no bad connection from PIN to SOCKET contact only connection (and resulting voltage drop etc.) will occur? (Upps, that might be a rhetorical / suggestive question)
Title: Re: MotherX4 Alternative for CPC 464 Users
Post by: TotO on 20:25, 25 October 19

The goal was to make something versatile for the different types of CPC mainboards (Edge, Centronics) and usages. Sure, putting directly the edge save a lot of soldering work, but that means the users have to raise the MotherX4 PCB too.
Title: Re: MotherX4 Alternative for CPC 464 Users
Post by: LambdaMikel on 20:28, 25 October 19
The goal was to make something versatile for the different types of CPC mainboards (Edge, Centronics) and usages. Sure, putting directly the edge save a lot of soldering work, but that means the users have to raise the MotherX4 PCB too.


See, that's a good point... every design is some compromise. For some anticipated most likely use case.
Now, I already tried that solution, and wasn't satisfied with it because it is very wanky. See picture attached. Also, that only worked because I removed the diode. I like to stress that everything I am saying is based on evidence and hard facts, not on dogma or "has to be".






Title: Re: MotherX4 Alternative for CPC 464 Users
Post by: TotO on 20:31, 25 October 19
The DDI-3 is heavy and not sat on the table... The official expansions does.

Here, you are using an edge adapter as well and some other peoples will put instead:
- MX4 to Edge ribbon
- MX4 to Centronics ribbon
- MX4 to MX4 ribbon
- MX4 to whatever ribbon
Title: Re: MotherX4 Alternative for CPC 464 Users
Post by: LambdaMikel on 20:34, 25 October 19
The DDI-3 is heavy and not sat on the table... The official expansions does.


Good. In general, I suggest to reduce the number of pin to socket contacts if possible though, because that's the weakest point. The width of VCC and GND tracks doesn't matter at all (we only have ONE VCC pin!) IF the IDC socket connection is wanky or loose.
Title: Re: MotherX4 Alternative for CPC 464 Users
Post by: TotO on 20:37, 25 October 19
I agree that is always better to not cumulate too much the connections.
Title: Re: MotherX4 Alternative for CPC 464 Users
Post by: LambdaMikel on 10:50, 26 October 19
https://oshpark.com/shared_projects/gfReKSs4
Title: Re: MotherX4 Alternative for CPC 464 Users
Post by: LambdaMikel on 20:01, 26 October 19

Here an alternative design based on the first version of the board (CTC-AY) : MotherX4_V2.1.zip (http://www.cpcwiki.eu/forum/amstrad-cpc-hardware/motherx4-alternative-for-cpc-464-users/?action=dlattach;attach=29820)

Is that a DIODE on the PCB there? If so, it better be optional...
Title: Re: MotherX4 Alternative for CPC 464 Users
Post by: robcfg on 20:15, 26 October 19
Probably as optional as the security belt on a car...


If everything goes right, there’s no difference, but the day something happens you wish you had it.
Title: Re: MotherX4 Alternative for CPC 464 Users
Post by: LambdaMikel on 20:22, 26 October 19
Probably as optional as the security belt on a car...
If everything goes right, there’s no difference, but the day something happens you wish you had it.

@robcfg (http://www.cpcwiki.eu/forum/index.php?action=profile;u=4)
I guess you don't know, but in the previous version it dropped the VCC so much that DDI3 would not work reliably at the end and the display was so dimm that it was unreadable... many people ended up removing it (the diode, not the DDI3).
So yes, there was a big difference.

http://www.cpcwiki.eu/forum/amstrad-cpc-hardware/mother-x4-and-ddi3-mods/msg162630/#msg162630 (http://www.cpcwiki.eu/forum/amstrad-cpc-hardware/mother-x4-and-ddi3-mods/msg162630/#msg162630)
Adding an extra PSU should not be necessary for 90 % of all CPC expansions (unless you have 10 or more or something crazy like that).
 
Title: Re: MotherX4 Alternative for CPC 464 Users
Post by: TotO on 21:14, 26 October 19
Well... Do you know about steering diode usages? Your board does nothing more than a SCSI ribbon cable.

When the MotherX4 was built in 2013, I have spoke with some electronicial peoples and they recommanded to add it.
First, because it is better than nothing to protect the CPC... Next, because one compensate the other if it goes weak, instead of failling.
Some peoples use the external PSU to save the content of a RAM Drive, can turn off the CPC power without disturbing the expansions...

In fact, the problem is for your kind of "arduino" modules that require to be 3V3 powered and your 5V to 3V3 regulator should not have enough voltage from the CPC itself.
The DDI-3 was never intended to be plugged at the end of the MotherX4 without an adapted external power supply... But directly on the CPC464 edge connector.
Need more voltage? Input more voltage!  :-\

Please, stop to focus on the MotherX4 dioles... It is a solution for around 250 happy users.
The problem is your dangerous fix posted on cpc-wiki :

(http://www.cpcwiki.eu/forum/index.php?action=dlattach;topic=14858.0;attach=25784;image)

Returning the external PSU current into the CPC VCC line...  :o
Please, clean behind your house first. Thanks.

@robcfg (http://www.cpcwiki.eu/forum/index.php?action=profile;u=4) From my tests, it is recommanded to use an external PSU if you are using more than three expansions, to save your CTM life.
Title: Re: MotherX4 Alternative for CPC 464 Users
Post by: robcfg on 21:22, 26 October 19
@LambdaMikel (http://www.cpcwiki.eu/forum/index.php?action=profile;u=2172) , don’t get me wrong, but diodes are not only there to drain voltage, but to protect from possible problems.


Now, if certain designs don’t take that into account, it’s a whole different issue.
Title: Re: MotherX4 Alternative for CPC 464 Users
Post by: LambdaMikel on 21:26, 26 October 19
@LambdaMikel (http://www.cpcwiki.eu/forum/index.php?action=profile;u=2172) , don’t get me wrong, but diodes are not only there to drain voltage, but to protect from possible problems.


Now, if certain designs don’t take that into account, it’s a whole different issue.
@robcfg (http://www.cpcwiki.eu/forum/index.php?action=profile;u=4), all I am suggesting is to put a jumper on board that disables this voltage dropping diode for people that do not require an extra PSU feeding into the MotherX4. I think you could understand that. You and I both know what a voltage protection diode is and what it's purpose is, yes.

Title: Re: MotherX4 Alternative for CPC 464 Users
Post by: LambdaMikel on 21:28, 26 October 19
Need more voltage? Input more voltage!  :-\
Unncessary and dangerous. Why add fire to the house if you don't need it.
Title: Re: MotherX4 Alternative for CPC 464 Users
Post by: LambdaMikel on 21:30, 26 October 19
Returning the external PSU current into the CPC VCC line...  :o
Please, clean behind your house first. Thanks.

What external PSU? Why would I put an external PSU to the CPC. It already has a PSU. I disabled and removed that unncessary connector.
Title: Re: MotherX4 Alternative for CPC 464 Users
Post by: LambdaMikel on 21:31, 26 October 19
Some people power a coffee maker from the Laptops USB port, or a fan, or a XMas tree.
In 2005, I spoke to Santa Claus, he likes the XMas tree USB powering!  :laugh:
Title: Re: MotherX4 Alternative for CPC 464 Users
Post by: TotO on 21:33, 26 October 19
C'est l'hopital qui se moque de la charité...  :laugh:
More serious... Forget me.
Title: Re: MotherX4 Alternative for CPC 464 Users
Post by: LambdaMikel on 21:35, 26 October 19
OK, I had enough fun now... Thanks. You made my day.  :)
Title: Re: MotherX4 Alternative for CPC 464 Users
Post by: TotO on 21:36, 26 October 19
OK, I had enough fun now... Thanks. You made my day.  :)
Please, return to your lego-electronics instead of criticising things your don't understand.
Title: Re: MotherX4 Alternative for CPC 464 Users
Post by: LambdaMikel on 21:44, 26 October 19
Please, return to your lego-electronics instead of criticising things your don't understand.
Yes, I know, I am not as clever as you (nor my designs), you told me before  ;D
Sorry for that.  :P
Title: Re: MotherX4 Alternative for CPC 464 Users
Post by: TotO on 21:47, 26 October 19
I'm currently sick, so I'm not very patient when someone always blames me the same thing ... Sorry.  :-*
Title: Re: MotherX4 Alternative for CPC 464 Users
Post by: LambdaMikel on 21:51, 26 October 19
Not blaming!! Suggesting improvements - but you probably don't see these suggestions as "improvements". I have reacted to your requests for improvements, because they made sense to me. I don't understand why it is such a big deal. If you don't like LambdaBoard and consider it a "clone" of MotherX4, then you could improve MotherX4 such that I could use it with DDI3, then I wouldn't have to make my own solution.  That means, you could add an edge connector directly to the end, and/or make the diode and PSU optional. I don't want an extra PSU to power it if it is known to be unnecessary. So, you either have to live with the fact that people create their own "solution" with their lego electronics understanding, or provide something that would address their problem. IMHO. Anyhow. Best wishes, get well!
Title: Re: MotherX4 Alternative for CPC 464 Users
Post by: robcfg on 22:24, 26 October 19
@robcfg (http://www.cpcwiki.eu/forum/index.php?action=profile;u=4), all I am suggesting is to put a jumper on board that disables this voltage dropping diode for people that do not require an extra PSU feeding into the MotherX4. I think you could understand that. You and I both know what a voltage protection diode is and what it's purpose is, yes.


Fair enough, I just hope the users are careful...
Title: Re: MotherX4 Alternative for CPC 464 Users
Post by: TotO on 22:24, 26 October 19
Sure... I have well understand. You want a board for your own usage, not a board for most users. ;D

I will not add directly the edge connector instead of the passthrough pins (will save my time) because already explained previously.
When peoples ask me for a MotherX4 and do not wants something, they let me know and I do... Or they buy it as kit to save euros.
The V2.1 linked previously do not have diodes but a sliding switch... It should make your day in a better way.  ;)

Quote
I just hope the users are careful...
I can't deal with that. I may have to fix things for less.  ???
Title: Re: MotherX4 Alternative for CPC 464 Users
Post by: LambdaMikel on 09:03, 27 October 19
The V2.1 linked previously do not have diodes but a sliding switch... It should make your day in a better way.  ;)
Yes, I like that. I probably won't buy a second one, but others might appreciate it.  :)