Hello, I have a DDI1 Clone of Zaxon (Piort Bugag)
Recently I have had problems accessing the floppy discs and I have encountered this disaster.
There is a displaced connecter in the female edge connecter. Seriously, I don't know how it could have happened and that it has only happened to this one. :picard2:
It looks like pin 29, according to the scheme
https://www.cpcwiki.eu/index.php/Connecter:Expansion_port
Does anyone know how to put the connecter in its place so that it can make contact again?
I don't know how to grab it to pull it
Any idea or any tool to recommend me?
Thank you very much in advance
You may change the connector ?
Stefan
It is an Edge connector.
If you have soldering skills you can replace it, they are cheap.
You could also try to unfold the pin to its approximate original position (if it doesn't broken), using electronics thin tweezers and small clock screwdrivers.
Although I see it more complicated than the substitution, so that this fixing could look good.
https://es.aliexpress.com/item/1005002212044956.html
Pin 29 is M1
Change the Connector
Good Luck
Keep Safe
Ray
Quote from: MoteroV4 on 23:25, 31 May 25It is an Edge connector.
If you have soldering skills you can replace it, they are cheap.
You could also try to unfold the pin to its approximate original position (if it doesn't broken), using electronics thin tweezers and small clock screwdrivers.
Although I see it more complicated than the substitution, so that this fixing could look good.
https://es.aliexpress.com/item/1005002212044956.html
Purchased and awaiting its arrival.
Thank you very much.
Does the CPC still work when the DDI is connected or would it be a complete failure then?
If that's a pure DDI-1 clone then the M1 signal should not be needed. If the pin is just gone and doesn't cause any short it should not have any impact on its functionality.
Then it would be a different fault and maybe not related to the connector.
Quote from: eto on 10:45, 01 June 25Does the CPC still work when the DDI is connected or would it be a complete failure then?
If that's a pure DDI-1 clone then the M1 signal should not be needed. If the pin is just gone and doesn't cause any short it should not have any impact on its functionality.
Then it would be a different fault and maybe not related to the connector.
CPC464 works and recognizes the drive. It even gives a "disk missing" error if the diskette isn't inserted, but a cat or |dir always says "bad command" error wih the disk inserted.
the disc spins in the meantime
Quote from: angelcaio on 14:06, 01 June 25CPC464 works and recognizes the drive. It even gives a "disk missing" error if the diskette isn't inserted, but a cat or |dir always says "bad command" error wih the disk inserted.
the disc spins in the meantime
Did you replace the drive belt?
Does the motor move the head?
See also these threads that talk about the "Bad Command" issue:
https://www.cpcwiki.eu/forum/amstrad-cpc-hardware/6128-disk-drive-issue/msg11131/#msg11131
https://www.cpcwiki.eu/forum/hardware-related/cpc-6128-returns-bad-command-on-cat/msg215240/#msg215240
I tried with varius drives
And this drives work fine in a 6128 in ds1 mode B: drive)
In 464 ds0
Quote from: angelcaio on 14:52, 01 June 25I tried with varius drives
And this drives work fine in a 6128 in ds1 mode B: drive)
In 464 ds0
Then check out the other posts. There are plenty of faults that can happen including faulty ROM, voltage issues (did you clean the contacts?) or broken traces but the M1 signal was never mentioned.
To be 100% sure you could check if the M1 signal is connected to any IC on the board.
Quote from: eto on 14:56, 01 June 25Quote from: angelcaio on 14:52, 01 June 25I tried with varius drives
And this drives work fine in a 6128 in ds1 mode B: drive)
In 464 ds0
Then check out the other posts. There are plenty of faults that can happen including faulty ROM, voltage issues (did you clean the contacts?) or broken traces but the M1 signal was never mentioned.
To be 100% sure you could check if the M1 signal is connected to any IC on the board.
Quote from: eto on 14:56, 01 June 25Quote from: angelcaio on 14:52, 01 June 25I tried with varius drives
And this drives work fine in a 6128 in ds1 mode B: drive)
In 464 ds0
Then check out the other posts. There are plenty of faults that can happen including faulty ROM, voltage issues (did you clean the contacts?) or broken traces but the M1 signal was never mentioned.
To be 100% sure you could check if the M1 signal is connected to any IC on the board.
Quote from: eto on 14:56, 01 June 25Quote from: angelcaio on 14:52, 01 June 25I tried with varius drives
And this drives work fine in a 6128 in ds1 mode B: drive)
In 464 ds0
Then check out the other posts. There are plenty of faults that can happen including faulty ROM, voltage issues (did you clean the contacts?) or broken traces but the M1 signal was never mentioned.
Para estar completamente seguro, podrías verificar si la señal M1 está conectada a algún circuito integrado en
Quote from: eto on 14:56, 01 June 25Quote from: angelcaio on 14:52, 01 June 25I tried with varius drives
And this drives work fine in a 6128 in ds1 mode B: drive)
In 464 ds0
Then check out the other posts. There are plenty of faults that can happen including faulty ROM, voltage issues (did you clean the contacts?) or broken traces but the M1 signal was never mentioned.
To be 100% sure you could check if the M1 signal is connected to any IC on the board.
It seems that it is not connected to any track
In another CC464 at a friend's house whit my ddi clone exactly the same thing happens :(
Update
I haven't received the 50-pin edge connectors yet, but I've checked each of the 49 live pins on the edge with the connection on the motherboard, and they all have continuity.
I remembered that the 5.25" drive's Molex connector (B:) sparked, but at the time, I didn't think anything of it. I think none of the drives have worked since then.
Could any component have been damaged? Can I check something?
Thanks
Quote from: angelcaio on 20:32, 03 June 25Could any component have been damaged? Can I check something?
Yes. Please follow the links to forum threads that I posted a couple of messages before.
In those threads a lot of potential issues and how to fix them has already been discussed.
If there was a spark, you probably fried one of the buffer IC's with a static discharge.
Bryce.
Thanks. Bryce
According to the original DDI-1 schematic, there are about eight of these components.
I don't know if I'm mistaken, or if they're all the same (74LS240), because some don't have anything written on them.
I've marked the ones I think are the same with a red X in case you can confirm this. I also don't know how to check them or if I should replace them all.
Or buy another DDI Clone model.
Edit. the numbers over the ic's are different and others are in blanks
Quote from: angelcaio on 11:16, 04 June 25Thanks. Bryce
According to the original DDI-1 schematic, there are about eight of these components.
I don't know if I'm mistaken, or if they're all the same (74LS240), because some don't have anything written on them.
I've marked the ones I think are the same with a red X in case you can confirm this. I also don't know how to check them or if I should replace them all.
Or buy another DDI Clone model.
Edit. the numbers over the ic's are different and others are in blanks
They are not all the same. Your picture is very blurry so it's hard to be 100% sure but if you look closely on the ICs you can identify the name on most of them. See picture attached for 3 that I think I could identify on your picture.
For those that really have no number it's hard to say. You could compare the PCB traces to the DDI schematics and check which connections are similar. Or if you do have an EPROM programmer like the TL-866 you can also use the feature to identify the type of IC.
You're right, Brice.
I took a closer look at the photos.
They look like:
SN74LS136N
SN74LS38N x 2
SN74LS74AN
SN74LS240N
SN74LS32N
SN74LS08N
SN74LS132N
SN74LS27N
Should I change anything else?
It will most likely be one of the two on the right hand side (between the 765 and the flat cable socket) that has failed.
Bryce.
Quote from: Bryce on 11:35, 05 June 25It will most likely be one of the two on the right hand side (between the 765 and the flat cable socket) that has failed.
Bryce.
Thanks very much,Bryce.
I'm going to order them. When I change them, I'll report
Hi, Bryce.
I received both ICs, SN74LS136N and SN74LS38N.
I swapped them (starting with the SN74LS136N), but the problem was still the same.
I desoldered the two wires from the SN74LS38N and bent and trimmed the pin ends. I put them in their socket and soldered them back to the wires.
And... IT WORKS!!!! with the two drives.
Thanks again for your help, Bryce.
After running it without any issues for a few days, today I left Parados loaded and went to the PC to write a disk with the CPC Disk XP. When I returned, I found the Parados screen distorted. I tried restarting it with the reset button on the DDI1 clone, but the screen only flickered. I turned it off and on again and found the screen of death, but it was filled with strange symbols. I turned it off and on again, and now all I see is the gray screen of death, both with and without the DDI1 clone connected.
Does anyone know what could have happened?
Could it have been caused by the DDI1 clone?
Thanks.
My first guess is RAM issue.
Stefan
There's a bad RAM chip in there somewhere.
Either inside the Zaxon DDI device or on your main board. Do a diagnostics on the latter and if that's all clear, it's time to put the DDI into the bin as it's causing more headaches than it is curing. :)
Was there ever Micron Technologies Ram inside the
CPCs? (μT on the chips) they were used quiet often by Atari and Commodore.
If so, replace all of them, in advance.
They WILL fail at some point.
Stefan
Quote from: Shaun M. Neary on 23:50, 20 June 25Either inside the Zaxon DDI device
This particular device is really just a DDI1 clone and does not contain any RAM.
Quote from: angelcaio on 22:48, 20 June 25Could it have been caused by the DDI1 clone?
I'm not an expert (let's wait for Bryce to confirm) but I would be surprised if the DDI could cause that. The internal RAMs are not directly connected to any lanes on the expansion bus.
But you should check the voltage that the CPC receives from the monitor if that's close to 5V or if it's maybe too high.
Quote from: eto on 21:19, 21 June 25Quote from: Shaun M. Neary on 23:50, 20 June 25Either inside the Zaxon DDI device
This particular device is really just a DDI1 clone and does not contain any RAM.
Quote from: angelcaio on 22:48, 20 June 25Could it have been caused by the DDI1 clone?
I'm not an expert (let's wait for Bryce to confirm) but I would be surprised if the DDI could cause that. The internal RAMs are not directly connected to any lanes on the expansion bus.
But you should check the voltage that the CPC receives from the monitor if that's close to 5V or if it's maybe too high.
5.16V
Everything's going wrong!!!!
I took my M4 to load Gerald's test ROM onto it.
https://www.cpcwiki.eu/forum/amstrad-cpc-hardware/quick-and-dirty-ram-test-for-cpc
I powered on the M4 board via USB, without connecting it to the CPC. Using the web interface, I loaded RAMTEXT.ROM into ROM 0 and enabled the lower ROM. I connected it to my CPC-464 and booted it up.
all green appears on the screen, border and paper as same and now the M4 doesn't even respond to pings or access the web.
Even disconnected from the CPC and powered by USB. :picard:
Only the blue LED next to R6 remains lit.
When the USB is connected to power, the green LED next to R14 flashes briefly and then turns off.
https://vimeo.com/1095356392?share=copy
Quote from: angelcaio on 09:14, 22 June 25Everything's going wrong!!!!
I took my M4 to load Gerald's test ROM onto it.
https://www.cpcwiki.eu/forum/amstrad-cpc-hardware/quick-and-dirty-ram-test-for-cpc
I powered on the M4 board via USB, without connecting it to the CPC. Using the web interface, I loaded RAMTEXT.ROM into ROM 0 and enabled the lower ROM. I connected it to my CPC-464 and booted it up.
all green appears on the screen, border and paper as same and now the M4 doesn't even respond to pings or access the web.
Even disconnected from the CPC and powered by USB. :picard:
Only the blue LED next to R6 remains lit.
When the USB is connected to power, the green LED next to R14 flashes briefly and then turns off.
https://vimeo.com/1095356392?share=copy
I have deleted all files ion M4 directory of SD Card and the M4 board it works again. Phew, what a relief!
Any advice on how to properly load the diagnostic ROM?
Quote from: angelcaio on 09:14, 22 June 25I loaded RAMTEXT.ROM into ROM 0
That "Lower-rom slot" field is the ROM slot you have to put the replacement lower-rom image into. So you should have put it into ROM 31, not ROM 0.
Lower-ROM enabled and the TEST ROM in slot 31, but it doesn't work until I press reset on the M4, while a screen appears with the paper and a dark green border.
My fault, I didn't notice this before. :picard:
Now it shows this. It seems the faulty chip is the last one. Is this the most significant or the least significant?
The service manual mentions eight 64 Kbit chips, from IC117 to IC124.
I don't know which one I should change.
Any idea?
Note: The ROM that finally worked for me is this one:
https://amstrad.es/forum/viewtopic.php?p=87827#p87827
Thanks
Quote from: angelcaio on 16:05, 22 June 25...
The service manual mentions eight 64 Kbit chips, from IC117 to IC124.
I don't know which one I should change. ...
What brand is it?
In case its
μT- Ram, i suggest you to change all at once. The question is not, if the RAM will fail,
but when it will.
Stefan
Quote from: angelcaio on 16:05, 22 June 25Note: The ROM that finally worked for me is this one:
Get the Amstrad Diagnostics Lower ROM:
https://github.com/llopis/amstrad-diagnostics/releases/tag/v1.3
IC numbers are then documented here:
https://github.com/llopis/amstrad-diagnostics/wiki
Thank you very much, I won't have access to 464 until next weekend.
I'll try this then
I was finally able to access my CPC464.
I set the lower ROMs to 31 and the higher ones to 0 on the M4 board.
The result is shown in the photos.
The chips are in different locations in the service manual and on my board.
I already ordered the sockets and chips with the same specifications: Samsung KM4164B-15.
Now I'm waiting for them to arrive.
By the way, I was impressed that even with a faulty IC, the image was displayed on the screen without any loss or corruption.
Superb work by Noel Llopis👏👏
Quote from: angelcaio on 08:07, 28 June 25The chips are in different locations in the service manual and on my board.
Seems the service manual shows the PCB from the bottom, so everything is mirrored. Not sure why they did that.
Quote from: angelcaio on 08:07, 28 June 25By the way, I was impressed that even with a faulty IC, the image was displayed on the screen without any loss or corruption.
Superb work by Noel Llopis👏👏
Yes, great job! No RAM is required for the initial test. As long as there is no real short on the motherboard it's possible to run the diagnostics.
I can't melt the tin! with a 400W soldering iron. :picard:
What material is this soldered with?
Is it a good idea to cut the pins and solder the socket to the ends of these? ....or is it better not to do it?
Thanks
Quote from: angelcaio on 16:12, 30 June 25I can't melt the tin! with a 400W soldering iron. :picard:
What material is this soldered with?
Your soldering iron should be able to reach about 300° at least. It might make sense to add some flux or new solder so the old solder can melt more easily.
I bought this on Amazon:
https://www.amazon.es/YIHUA-858D-soldadura-desoldadura-temperatura/dp/B0BYSKPJQX/ref=sr_1_15?dib=eyJ2IjoiMSJ9.d6CCwzT7t1oLYMJLpE4B1roSUYGG6bXI8N9_W_Te5ok9RDZJetUEJ1s5KJ9lUReJgoUogR1ryhWJCSSx1vSvUc5iRTNB--HNUjlOwSRlbGMU1HfdXzRzg0tRJefa_JIrvSyICWC1RLJi58shkuv59v51S_vvQkATlT3fn-hwWq5IzmhWzxyHPzcEuIgLk7rY61qJjF8glGcJxA1Ae_T8Y2nk8mTZLRCeUW2Fsx6LdDg.C5gtdTpod8knq_u3fM7YLf4h3P8jt7IoAggjDUs2J_I&dib_tag=se&qid=1751293551&s=tools&sr=1-15
Maybe it will help to desolder... and resolder....
With this hot air soldering iron, it was quite easy to remove the chip. Then we soldered a socket and inserted the DIP memory chip... et voilà! It works again!
Thanks to everyone for your support!
Quote from: eto on 21:19, 21 June 25Quote from: Shaun M. Neary on 23:50, 20 June 25Either inside the Zaxon DDI device
This particular device is really just a DDI1 clone and does not contain any RAM.
Quote from: angelcaio on 22:48, 20 June 25Could it have been caused by the DDI1 clone?
I'm not an expert (let's wait for Bryce to confirm) but I would be surprised if the DDI could cause that. The internal RAMs are not directly connected to any lanes on the expansion bus.
But you should check the voltage that the CPC receives from the monitor if that's close to 5V or if it's maybe too high.
Honestly, I'm hesitant to connect the DDI1 clone. Would it be a good idea to try it?Everything worked fine for two or three days after the DDI repair and before the RAM (IC120) D0 failed. Is there anything i can do beforehand ton be sure?Is IC0 connected to pin 26 in edge connector?Thank