Repairing a broken Archimedes A3000 ... Update 14.05.17 - mouse progress - the mouse fully works too! I think, it's done

[YuT666]

Yes, still the same.

EDIT:

*UNPLUG

... shows a huge list.

*RMREINIT DESKTOP

*MODULES

... the Desktop is listed too, but when i type:

*DESKTOP

... i get an error:

SWI &400F2

[DutchAcorn]

...The place of the battery leakage looks ok, but not as good as i expected. Soldered two pins for the battery and a socket for the new CMOS IC.

...

Well, the CMOS does not work yet, so this will be the next problem to solve...

Progress!

From the picture it looks like the track from pin 2 to X2 is damaged, have you checked conductivity between pins 1 and 2 and the legs of X2?
Do you measure 3-5V across pins 8 and 4?
Is there conductivity between IC6 pin 5 and IC13 pin 44? (C0)
Is there conductivity between IC6 Pin 6 and IC13 pin 45? (C1)

[DutchAcorn]

Having another look at the picture of the PCB after cleanup there seems to be some obvious track damage (marked red) and some suspect tracks (marked orange).

The track just above R7 is not vital for CMOS operation but you will need it if you want to fit a replacement battery.

[Zarchos]

Great to read there's hope.
I don't know if you've got 4 Mbytes in your Archie, but at the moment some cheap memory upgrades are listed by IFEL on EBay ...

[Andy1979]

Pleased to see your persistence with the keyboard has paid off

If there was track damage to the keyboard it is likely the same is true of the CMOS circuit. As others have said, should be repairable in the same way as the keyboard.

Failing that, when researching the same topic before retrieving my old A3010 recently I came across this module which replaces the onboard CMOS circuit entirely. Does tie up (some of) the minipodule connector though http://www.cjemicros.co.uk/micros/products/rtc.shtml

Personally I'd try to repair the original circuit - you obviously have the skills, and the patience! Good luck.

[YuT666]

Thanks to you all ...

@DutchAcorn:

Great, i'll check the tracks when i'm at home.

@Zarchos:

Looks like a good alternative to the more expensive SIMTEC. I bought an adapter and i think, that i've some old 4MB SIMMs for a test.

@Andy1979:

Well, my soldering skills are only fair and i have a really hot temper (sometimes i want to throw the crap through the closed window), but ... my goal is to repair this Arc ... absolutely.

The link you gave me would be a good possibilty if my efforts will fail.

[MSuomi]

Hello all!

Excellent thread here! As I'm in exactly the same state as the YuT666!

I bought an broken A3000, which arrived today (have been interested on machine my whole life, first time I see one in real life, here in Finland it was basically non-existent machine). The problem was, that it only boots to Supervisor. There were pictures from the motherboard, so I saw someone had replaced the battery and I though it couldn't be a big problem.

So I disassembled machine straight away. Firstly I saw, that the new battery was made by installing AA-battery into battery holder (well, I saw this already when I was looking pictures of it), which was cracked (this I didn't see on picture). So probably no proper contact, I just quickly fixed it with tape and installed a new rechargeable battery, just in case. Made a reset and as was described, it still boots straight into supervisor. Listing modules gave me 1 result, so after reading different forums I started to look at CMOS-chip (PCF8583P). I then took a better look at motherboard and saw, that it was not properly cleaned, though the corrosion is very mild compared to many pictures I have seen... So I cleaned it with vinegar-solution, but I'm still having same problems (exactly) as YuT666. There is some marks of leakage on the keyboard connector and occasionally some characters don't work and I cannot start it to anywhere, but Supervisor. As those CMOS-chips are cheap, I already ordered 3 of them. In the following week, I will get the motherboard totally out of the case and examine it on both sides, checking traces and so on.

I already have to thank everyone who has contributed to this thread, as I got excellent information for what to look! I surely hope I can repair my Archie back to working order and check out, what I have wanted to get to know for so long time

[Zarchos]

Thanks to you all ...

[SNIP]
Well, my soldering skills are only fair and i have a really hot temper (sometimes i want to throw the crap through the closed window), but ... my goal is to repair this Arc ... absolutely.

[SNIP].

Hot temper... you mean ?
Like this ?

I opened the kitchen's door, and finished it with a screw driver and my hands ...

Antoine.png (14.84 KiB) Viewed 106 times

[daveejhitchins]

First - Welcome to the Forum, MSuomi . . . Enjoy . . .

Next - Have you reset the CMOS by holding the DELETE key down when powering up - keep it held down until everything settles.

Dave H

[MSuomi]

First - Welcome to the Forum, MSuomi . . . Enjoy . . .

Next - Have you reset the CMOS by holding the DELETE key down when powering up - keep it held down until everything settles.

Dave H

Thanks.

Yes, it resets but still goes straight to supervisor. Just as in YuT666's case. The middle trace of the 3 traces from the top of CMOS-chip might be broken, as I don't see solder-ring on top of it (at the end of the trace, where there is inlet/duct). I cannot dive into it properly, until next week...

[daveejhitchins]

The middle trace of the 3 traces from the top of CMOS-chip might be broken, as I don't see solder-ring on top of it (at the end of the trace, where there is inlet/duct). I cannot dive into it properly, until next week...

Sounds like you've a few links to attach - Your A3000 will be joining a club that seems to be the norm, these days. I've several A3000s in the same state - all waiting for track replacements! One day . . .

Dave H

[YuT666]

@MSuomi:

Well, it would be better to start a new thread, 'cause this are two different cases (maybe similar faults, but other brocken tracks and other stuff). It is a bit confusing and starting a new one for you would be easier to follow. Thanks.

@Zarchos:

Yes, i think i'm acting similar ... but here i've to cool down.

@Topic:

I'm back from work, time to play with my little son and after that ... i'll measure the CMOS tracks.

[MSuomi]

@MSuomi:

Well, it would be better to start a new thread, 'cause this are two different cases (maybe similar faults, but other brocken tracks and other stuff). It is a bit confusing and starting a new one for you would be easier to follow. Thanks.

Don't worry, I'm not going to steal the thread
Just had to express a gratitude, about all the info I gathered from this thread
If I need to ask more about my case, I'll surely make a new thread.

[YuT666]

No problem, it's only for the clarity ...

I'll help you to solve your probs too ... if i can. I'm relatively new to the Arc thing, but the guys here are absolutely great.

[YuT666]

@DutchAcorn: I measured some tracks and the ones leading to X2 are ok. But i've question ...

You wrote, that i measure IC6 pin 5 and 6 to C0 and C1, so here are some pics.

This is the soldered side.

So this should be the right pins 5 & 6 - and C0 and C1 are above? These two soldering points are leading to IC13.

The front.

This ones should be connected? Am i right or absolutely wrong?

[DutchAcorn]

That seems right. But to check you can measure conductivity between the solder points and the corresponding pins on IC13:

[YuT666]

Ok, there is no conductivity. Both tracks seem to be broken (the top of the board).

So soldering two wires (the red lines at the back) should solve the problem?

[DutchAcorn]

Ok, there is no conductivity. Both tracks seem to be broken (the top of the board).

So soldering two wires (the red lines at the back) should solve the problem?

Can you check that the left track going up in the picture actually goes to IC13 pin 44 and the right track goes to IC13 pin 45?

[YuT666]

Yes, both are leading to IC13.

[DutchAcorn]

Yes, both are leading to IC13.

But do they lead to the corresponding pins on IC13?

[YuT666]

Yes ...

[DutchAcorn]

Then go for it!

[YuT666]

It's not nice, but the CMOS IC is "connected" with the IOC.

I'll test this configuration.

[DutchAcorn]

I'm afraid there are more tracks to fix, but it can't hurt to test...

[YuT666]

What da hell ... a further progress! Powered on while holding DELETE ...

[DutchAcorn]

Excellent!

I am pleasantly surprised that the CMOS chip also gets powered
If holding DEL works then the CMOS circuit works. It should now hold and remember configuration options.
... Until you leave it switched off for a while...


It looks as though fitting a new battery needs another track fixed but for now it is probably a good idea to check if the computer behaves. Does it read floppies?

[YuT666]

I must connect the floppy drive first. I don't have any Acorn disks, so i have to create some with omniflop.

[DutchAcorn]

In all fairness I am not really concerned about floppy operation. The critical circuits around the battery for the A3000 are CMOS and keyboard and you have covered both...

It may be it may be fun to see if the Cumana 1->2 MB memory upgrade works (as shown in the first post). I assume it was removed for testing?

[YuT666]

I'll test the Cumana memory soon ... yes, i removed it, 'cause testing and soldering was easier without.

But a further "bigger" problem is ... i don't have a mouse and the "original" mice are ereally xpensive. I visited many pages with self made adapters and other stuff and i've to figure it out, what will be the best solution.

[Zarchos]

If you need an Archie mouse connector I can send you one.
You did a great job with this Archie !