2x A4000 board problem

Yod@ · 10 July 2005, 09:39

Thought I'd start a new thread since it's no longer a Picasso II problem, and there's a second board involved now.

Both A4000 boards had corrosion caused by a leaky battery, and I've managed to get both of them to power up now.
However, one of them takes about 30 seconds longer to boot than it used to (just sits on a black screen for AGES before the "chime" sound and eventually the disk prompt animation finally comes up). The delay is still present regardless of a cold boot or warm reset.

The other board powers up but either sits on a black screen, or else gives a purple screen or a recoverable alert (no 30 second delay yet).

Anybody got any ideas? I've started changing some of the capacitors on the boards, but I've no idea if I'm even on the right track.

EDIT: I've already tried changing RAM, CPUs, Kickstart ROMs etc with no effect so I know they're definitely board problems.

DoctorQ · 10 July 2005, 10:02

What is connected to the motherboards? If possible, I would strip down the motherboards to only have a daughterboard and the CPU card installed, no floppy, no hdd, nothing else than the daughterboard and the CPU card.

IIRC Kickstart 3.1 takes longer to boot the computer compared to Kickstart 3.0. A boot delay occurs for instance when a floppy drive isn't installed which could be caused by an improper installed floppy cable. You can always trick the motherboard into thinking that a floppy drive installed by putting a jumper on pin 1 + 2 on the floppy header on the motherboard.

If the motherboards still act up, I don't know what to do. As I'm not an electronics wiz I can't tell you if you are on the right track with what you are doing now. However, the above mentioned method has a good troubleshooting method to me.

Yod@ · 10 July 2005, 10:06

Once again, thanks for your quick reply.

I just have a bare PSU, the motherboard(s), a stick of (chip) ram, and a CPU daughterboard connected up.

I guess the long delay could simply be because I haven't connected the floppy drive!
I'll test it out now, thanks!

Yod@ · 10 July 2005, 10:18

I connected up a floppy drive (and booted a disk to make sure it was all working ok), but it didn't affect the delay.

If I reboot and hold both mouse buttons, I still have to wait about 30 seconds before the Early Startup screen comes up.

I've tried swapping my 3.0 and 3.1 roms over, and the delay seems to be the same.

Thanks for the help anyway, any other suggestions will also be greatly appreciated. I guess I might just have to continue replacing caps etc in the meantime.

DoctorQ · 10 July 2005, 10:20

Just put a jumper on it, it is the easiest way to do it.

If you have a bootable partition with a plain OS3.0 installed, and are using a A3630 board as CPU card I would stick the harddrive in as well. It should boot the Workbench right away then. If you are using a A3640 CPU card, then keep in mind to install the 68040 library, otherwise there is a chance it will GURU.

DoctorQ · 10 July 2005, 10:36

Actually, I think 30 seconds is about normal for an Amiga 4000 to boot if no harddrive is connected to the IDE controller. You can either install a IDE drive on the controller or search for the NoIDE hack on Aminet. The ReadMe for the hack has some interesting information about boot times. See it here http://main.aminet.net/disk/misc/NoIDE13.readme

-EDIT-

Sorry, this should be what you need, if you temporarily want to disable your IDE controller.
http://main.aminet.net/hard/hack/no4000ide.readme

Yod@ · 10 July 2005, 11:00

Quote:

Originally Posted by DoctorQ

Actually, I think 30 seconds is about normal for an Amiga 4000 to boot if no harddrive is connected to the IDE controller.

You're a genius. This board seems to be working perfectly now that the floppy and hard drive are both connected.

I really should have asked this question yesterday and saved myself hours of pointless work!

Thanks again for your help, DoctorQ; you've saved one of my A4000s.

DoctorQ · 10 July 2005, 12:01

No problem, I´m glad you got it working. Is everything working then? Display, audio, clock, floppy, hdd, zorro slots?

Yod@ · 10 July 2005, 12:22

Display, audio, floppy, hard drive, mouse all working.
I haven't rebuilt the machine yet so haven't been able to test the Zorro slots yet, and I had to just remove the leaky battery.

I'm just sorting through a whole bunch of SIMMs to try and find a set of working memory to put in it. Once I've done that, I'll solder a normal CR2032 battery to the board (with a diode to prevent the board from trying to charge a non-rechargeable battery and exploding it!).
I'm not very worried about the lack of a clock though.

Yod@ · 10 July 2005, 18:01

Gah. I soldered a CR2032 socket onto the board with a diode, had the clock all working fine, found 96Mb of working SIMMs for the board and had everything working perfectly - so I rebuilt the machine, and now my PSU is dead.

I'll have to wire up a PC PSU later.

DoctorQ · 10 July 2005, 18:18

Isn´t that just typical?

Yod@ · 11 July 2005, 20:30

Managed to replace the blown PSU with a PC one last night, and spent ages today setting up the Picasso IV/network card etc. Here are my results...

http://img.photobucket.com/albums/v2...yoda/Black.jpg
http://img.photobucket.com/albums/v2.../BlackOpen.jpg
http://img.photobucket.com/albums/v2...yoda/White.jpg
http://img.photobucket.com/albums/v2.../WhiteOpen.jpg
http://img.photobucket.com/albums/v2...yoda/Boing.jpg

There are a few things on the second faulty board which I'd missed, so there's still a chance that I may be able to get it working.

Thanks again to all who helped me with this, if anybody has a similar battery corrosion problem I'd be happy to give advice on repairing it.

lopos2000 · 11 July 2005, 21:09

@Yod
Did you use an ATX or AT PSU? I have the same problem in replacing an A4000D Psu with an ATX PSU. BTW nice towers. Wish I had one.

Yod@ · 11 July 2005, 21:25

I used an ATX one. An AT one would have been easier, but I couldn't really find a suitable way to fix the power switch to the button on the front of the case.

You should see the way it worked with the original PSU - the power switch was located on the PSU itself, and there was a long plastic rod joining the power button at the front of the case to the switch at the rear of the case!

lopos2000 · 11 July 2005, 21:38

The problem is that the ATX PSU are all to big (to wide). So, I am still looking for a suitable PSU which will fit into an A4000D. I tried to put an ATX PSU board into the Amiga PSU but it's 2mm to big. Did you solder the 6 wires from A4000 PSU plug straight onto the PSU board and removed all the unused wires?

Yod@ · 11 July 2005, 21:59

Ah, I've never seen an A4000D, so I'm not sure of the dimensions of the PSU required for that.

If it's any help, the replacement PSU I'm using is fairly small (I pulled it out of a minitower PC).

I opened up the faulty Amiga PSU (be careful, there are high-voltage capacitors in there which can hold a hefty charge), and cut out all the wires.

Then I cut the ATX connector off the PC PSU, completely removed all the wires which I didn't need, and then just soldered the wires from the ATX PSU onto the relevant wires of the Amiga power connector.
One ground wire and the green ATX wire were wired up to a latching power switch for the main power button.

Here's a picture - you can see the original PSU at the bottom (I had to keep it because of that ridiculous power switch configuration!), and the new (smaller) PSU above it.
At the left of the picture you can see where I cut and spliced the power cables (used heatshrink to cover them), and the motherboard connector at the end on the right.
You'll see the green wire as well - that's connected to the power switch of the bottom (now empty) PSU. As long as the green wire is grounded, the ATX PSU will provide power.
I did consider actually leaving the green wire connected to ground, and using the main power switch on the PSU to turn it on and off, but I thought it would be a bit awkward to get at.

http://img.photobucket.com/albums/v2...a/AmigaPSU.jpg

If you let me know the dimensions of your existing PSU, I'll have a look and see if it's possible to get replacement PC PSUs of that size.

lopos2000 · 11 July 2005, 22:11

Looks very crowded in your tower. Here are the dimenson of the A4000D PSU.
H: 11.5 cm
W: 12.5 cm
D: 17 cm
Most ATX PSU are W:15 cm which is the problem. Anyway, thanks for your help.

BTW. I did find out the hard way about the high-voltage capacitors. Discharged them via my body.

Autsch, that hurt.

DoctorQ · 11 July 2005, 22:30

@Yod@

take a look at this site

http://www.ianstedman.co.uk/Amiga/am..._supplies.html

Seeing that you are quite skilled with a soldering iron, you should be able to build the circuit on the page, and then be able to ditch the old PSU. It´s a MicroniK big tower, right?

Unfortunately I´m not that skilled with a soldering iron, I need to builf such a board myself for my A1200/Mediator/PPC :-(

Yod@ · 12 July 2005, 01:24

Thanks for the link, I did come across that circuit while I was checking pinouts etc actually - however, my problem is that I couldn't see any simple way of physically connecting a switch directly to the button on the front of the case.

If I had a switch at the front, I'd have had no trouble with the rest of the wiring/electronics. I really wanted to get it all sorted out quickly, so that's why I just decided to use the old switch.

When I get a chance, I'll go back and try to find a more elegant way of connecting it up.

And yeah, I think it's a MicroniK tower (at least, it has MicroniK printed on the busboard). I'm very familiar with standard A500/A600/A1200 hardware, but this is the first time I've come across an A4000 or a tower Amiga - that's why I don't know anything about it.

10 July 2005, 09:39	#1
Yod@ Registered User Join Date: May 2005 Location: Bangor, N. Ireland Age: 47 Posts: 74	2x A4000 board problem Thought I'd start a new thread since it's no longer a Picasso II problem, and there's a second board involved now. Both A4000 boards had corrosion caused by a leaky battery, and I've managed to get both of them to power up now. However, one of them takes about 30 seconds longer to boot than it used to (just sits on a black screen for AGES before the "chime" sound and eventually the disk prompt animation finally comes up). The delay is still present regardless of a cold boot or warm reset. The other board powers up but either sits on a black screen, or else gives a purple screen or a recoverable alert (no 30 second delay yet). Anybody got any ideas? I've started changing some of the capacitors on the boards, but I've no idea if I'm even on the right track. EDIT: I've already tried changing RAM, CPUs, Kickstart ROMs etc with no effect so I know they're definitely board problems. Last edited by Yod@; 10 July 2005 at 10:24.

10 July 2005, 12:22	#9
Yod@ Registered User Join Date: May 2005 Location: Bangor, N. Ireland Age: 47 Posts: 74	Display, audio, floppy, hard drive, mouse all working. I haven't rebuilt the machine yet so haven't been able to test the Zorro slots yet, and I had to just remove the leaky battery. I'm just sorting through a whole bunch of SIMMs to try and find a set of working memory to put in it. Once I've done that, I'll solder a normal CR2032 battery to the board (with a diode to prevent the board from trying to charge a non-rechargeable battery and exploding it!). I'm not very worried about the lack of a clock though. Last edited by Yod@; 10 July 2005 at 13:28.

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10 July 2005, 10:02	#2
DoctorQ What?? Who?? DoctorQ!! Join Date: Jun 2005 Location: Rødding/Denmark Age: 43 Posts: 314	What is connected to the motherboards? If possible, I would strip down the motherboards to only have a daughterboard and the CPU card installed, no floppy, no hdd, nothing else than the daughterboard and the CPU card. IIRC Kickstart 3.1 takes longer to boot the computer compared to Kickstart 3.0. A boot delay occurs for instance when a floppy drive isn't installed which could be caused by an improper installed floppy cable. You can always trick the motherboard into thinking that a floppy drive installed by putting a jumper on pin 1 + 2 on the floppy header on the motherboard. If the motherboards still act up, I don't know what to do. As I'm not an electronics wiz I can't tell you if you are on the right track with what you are doing now. However, the above mentioned method has a good troubleshooting method to me.

10 July 2005, 10:06	#3
Yod@ Registered User Join Date: May 2005 Location: Bangor, N. Ireland Age: 47 Posts: 74	Once again, thanks for your quick reply. I just have a bare PSU, the motherboard(s), a stick of (chip) ram, and a CPU daughterboard connected up. I guess the long delay could simply be because I haven't connected the floppy drive! I'll test it out now, thanks!

10 July 2005, 10:18	#4
Yod@ Registered User Join Date: May 2005 Location: Bangor, N. Ireland Age: 47 Posts: 74	I connected up a floppy drive (and booted a disk to make sure it was all working ok), but it didn't affect the delay. If I reboot and hold both mouse buttons, I still have to wait about 30 seconds before the Early Startup screen comes up. I've tried swapping my 3.0 and 3.1 roms over, and the delay seems to be the same. Thanks for the help anyway, any other suggestions will also be greatly appreciated. I guess I might just have to continue replacing caps etc in the meantime.

10 July 2005, 10:20	#5
DoctorQ What?? Who?? DoctorQ!! Join Date: Jun 2005 Location: Rødding/Denmark Age: 43 Posts: 314	Just put a jumper on it, it is the easiest way to do it. If you have a bootable partition with a plain OS3.0 installed, and are using a A3630 board as CPU card I would stick the harddrive in as well. It should boot the Workbench right away then. If you are using a A3640 CPU card, then keep in mind to install the 68040 library, otherwise there is a chance it will GURU.

10 July 2005, 10:36	#6
DoctorQ What?? Who?? DoctorQ!! Join Date: Jun 2005 Location: Rødding/Denmark Age: 43 Posts: 314	Actually, I think 30 seconds is about normal for an Amiga 4000 to boot if no harddrive is connected to the IDE controller. You can either install a IDE drive on the controller or search for the NoIDE hack on Aminet. The ReadMe for the hack has some interesting information about boot times. See it here http://main.aminet.net/disk/misc/NoIDE13.readme -EDIT- Sorry, this should be what you need, if you temporarily want to disable your IDE controller. http://main.aminet.net/hard/hack/no4000ide.readme

10 July 2005, 12:01	#8
DoctorQ What?? Who?? DoctorQ!! Join Date: Jun 2005 Location: Rødding/Denmark Age: 43 Posts: 314	No problem, I´m glad you got it working. Is everything working then? Display, audio, clock, floppy, hdd, zorro slots?

10 July 2005, 18:01	#10
Yod@ Registered User Join Date: May 2005 Location: Bangor, N. Ireland Age: 47 Posts: 74	Gah. I soldered a CR2032 socket onto the board with a diode, had the clock all working fine, found 96Mb of working SIMMs for the board and had everything working perfectly - so I rebuilt the machine, and now my PSU is dead. I'll have to wire up a PC PSU later.

10 July 2005, 18:18	#11
DoctorQ What?? Who?? DoctorQ!! Join Date: Jun 2005 Location: Rødding/Denmark Age: 43 Posts: 314	Isn´t that just typical?

11 July 2005, 20:30	#12
Yod@ Registered User Join Date: May 2005 Location: Bangor, N. Ireland Age: 47 Posts: 74	Managed to replace the blown PSU with a PC one last night, and spent ages today setting up the Picasso IV/network card etc. Here are my results... http://img.photobucket.com/albums/v2...yoda/Black.jpg http://img.photobucket.com/albums/v2.../BlackOpen.jpg http://img.photobucket.com/albums/v2...yoda/White.jpg http://img.photobucket.com/albums/v2.../WhiteOpen.jpg http://img.photobucket.com/albums/v2...yoda/Boing.jpg There are a few things on the second faulty board which I'd missed, so there's still a chance that I may be able to get it working. Thanks again to all who helped me with this, if anybody has a similar battery corrosion problem I'd be happy to give advice on repairing it.

11 July 2005, 21:09	#13
lopos2000 Zone Friend Join Date: Apr 2005 Location: Cider is best In The West Posts: 1,238	@Yod Did you use an ATX or AT PSU? I have the same problem in replacing an A4000D Psu with an ATX PSU. BTW nice towers. Wish I had one.

11 July 2005, 21:25	#14
Yod@ Registered User Join Date: May 2005 Location: Bangor, N. Ireland Age: 47 Posts: 74	I used an ATX one. An AT one would have been easier, but I couldn't really find a suitable way to fix the power switch to the button on the front of the case. You should see the way it worked with the original PSU - the power switch was located on the PSU itself, and there was a long plastic rod joining the power button at the front of the case to the switch at the rear of the case!

11 July 2005, 21:38	#15
lopos2000 Zone Friend Join Date: Apr 2005 Location: Cider is best In The West Posts: 1,238	The problem is that the ATX PSU are all to big (to wide). So, I am still looking for a suitable PSU which will fit into an A4000D. I tried to put an ATX PSU board into the Amiga PSU but it's 2mm to big. Did you solder the 6 wires from A4000 PSU plug straight onto the PSU board and removed all the unused wires?

11 July 2005, 21:59	#16
Yod@ Registered User Join Date: May 2005 Location: Bangor, N. Ireland Age: 47 Posts: 74	Ah, I've never seen an A4000D, so I'm not sure of the dimensions of the PSU required for that. If it's any help, the replacement PSU I'm using is fairly small (I pulled it out of a minitower PC). I opened up the faulty Amiga PSU (be careful, there are high-voltage capacitors in there which can hold a hefty charge), and cut out all the wires. Then I cut the ATX connector off the PC PSU, completely removed all the wires which I didn't need, and then just soldered the wires from the ATX PSU onto the relevant wires of the Amiga power connector. One ground wire and the green ATX wire were wired up to a latching power switch for the main power button. Here's a picture - you can see the original PSU at the bottom (I had to keep it because of that ridiculous power switch configuration!), and the new (smaller) PSU above it. At the left of the picture you can see where I cut and spliced the power cables (used heatshrink to cover them), and the motherboard connector at the end on the right. You'll see the green wire as well - that's connected to the power switch of the bottom (now empty) PSU. As long as the green wire is grounded, the ATX PSU will provide power. I did consider actually leaving the green wire connected to ground, and using the main power switch on the PSU to turn it on and off, but I thought it would be a bit awkward to get at. http://img.photobucket.com/albums/v2...a/AmigaPSU.jpg If you let me know the dimensions of your existing PSU, I'll have a look and see if it's possible to get replacement PC PSUs of that size.

11 July 2005, 22:11	#17
lopos2000 Zone Friend Join Date: Apr 2005 Location: Cider is best In The West Posts: 1,238	Looks very crowded in your tower. Here are the dimenson of the A4000D PSU. H: 11.5 cm W: 12.5 cm D: 17 cm Most ATX PSU are W:15 cm which is the problem. Anyway, thanks for your help. BTW. I did find out the hard way about the high-voltage capacitors. Discharged them via my body. Autsch, that hurt.

11 July 2005, 22:30	#18
DoctorQ What?? Who?? DoctorQ!! Join Date: Jun 2005 Location: Rødding/Denmark Age: 43 Posts: 314	@Yod@ take a look at this site http://www.ianstedman.co.uk/Amiga/am..._supplies.html Seeing that you are quite skilled with a soldering iron, you should be able to build the circuit on the page, and then be able to ditch the old PSU. It´s a MicroniK big tower, right? Unfortunately I´m not that skilled with a soldering iron, I need to builf such a board myself for my A1200/Mediator/PPC :-(

12 July 2005, 01:24	#19
Yod@ Registered User Join Date: May 2005 Location: Bangor, N. Ireland Age: 47 Posts: 74	Thanks for the link, I did come across that circuit while I was checking pinouts etc actually - however, my problem is that I couldn't see any simple way of physically connecting a switch directly to the button on the front of the case. If I had a switch at the front, I'd have had no trouble with the rest of the wiring/electronics. I really wanted to get it all sorted out quickly, so that's why I just decided to use the old switch. When I get a chance, I'll go back and try to find a more elegant way of connecting it up. And yeah, I think it's a MicroniK tower (at least, it has MicroniK printed on the busboard). I'm very familiar with standard A500/A600/A1200 hardware, but this is the first time I've come across an A4000 or a tower Amiga - that's why I don't know anything about it.

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