New (to me) A3000

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trixster
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New (to me) A3000

Postby trixster » Fri Feb 10, 2017 1:57 pm

I've finally bought an A3000! It arrived this morning. It's a little yellower than I'd have hoped but other than that the case is in really good condition.

The first thing I did was take it apart to see if there's a battery leakage horror show.
IMG_3967.JPG


The battery was still there and it didn't look tooooo bad in the surrounding area.

I removed the battery.
IMG_3968.JPG

IMG_3969.JPG


Most of the c*** was relatively easy to get rid of. I then used some spirit vinegar on cotton tips to try and tackle the gunk. Some of the fizzing as the vinegar acid tackled the battery alkaline was quite impressive! I then went over the areas again with cotton buds soaked in Isopropyl alcohol.

IMG_3970.JPG


It could be better but I think that's the best I can do.
A3020 | A3000 | A420/1 | BBC B + 128K RAM/ROM + 20K Shadow + Pi0 + VideoNuLA
Master Turbo + DC + BeebSID | Atom | A4000 060 | A3000 060 | A1200 060 | A500
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Re: New (to me) A3000

Postby trixster » Fri Feb 10, 2017 2:04 pm

It was only then that I realised it had a memory upgrade

IMG_3971.JPG


An MA4D IFEL board. I think it's 4mb

I thought I'd got a spare varta mempac 3.6 battery pack as I'm sure I'd bought 2 when I fitted one last year to the A3020 but I can't find it! So I've ordered another one.

Similarly I thought I had a suitable 9pin to 15pin vga adapter but it turns out it's female on the 9pin end and needs to be male. So one of those and a battery are on order!

Next was to see if she booted correctly which would be tricky without a monitor.

I got the following error code: 00020101

This I think equates to:

RAM control line failure
CMOS RAM checksum error
Self-test due to power-on

I turn on and off again with delete held to try and clear the cmos. No joy. So with the ram line failure in mind I removed the IFEL ram board. Hey presto she boots with a beep!

So I'm hoping she's ok. Can't really tell until I get the adapter to hook the monitor up.

Is the ram failure occurring because of the lack of battery? Or could it be a faulty motherboard or ram upgrade?
A3020 | A3000 | A420/1 | BBC B + 128K RAM/ROM + 20K Shadow + Pi0 + VideoNuLA
Master Turbo + DC + BeebSID | Atom | A4000 060 | A3000 060 | A1200 060 | A500
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Re: New (to me) A3000

Postby zeem » Fri Feb 10, 2017 2:27 pm

From personal experience, in order of likelihood:

1) RAM expansion will need removing and re-inserting a few times, as the pins may be tarnished with age (and possibly the corrosive atmosphere inside the case, caused by the leaking battery)
2) Faulty RAM chips on the expansion board
3) Motherboard fault, possibly caused by the leaking battery

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Re: New (to me) A3000

Postby trixster » Fri Feb 10, 2017 2:42 pm

I've just had a thought. The A3000 has mono composite out, and my monitors have composite in! Where's that old composite cable - ah, there it is!

Et voila

IMG_3973.JPG
A3020 | A3000 | A420/1 | BBC B + 128K RAM/ROM + 20K Shadow + Pi0 + VideoNuLA
Master Turbo + DC + BeebSID | Atom | A4000 060 | A3000 060 | A1200 060 | A500
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Re: New (to me) A3000

Postby trixster » Fri Feb 10, 2017 2:55 pm

And more importantly

IMG_3974.JPG
A3020 | A3000 | A420/1 | BBC B + 128K RAM/ROM + 20K Shadow + Pi0 + VideoNuLA
Master Turbo + DC + BeebSID | Atom | A4000 060 | A3000 060 | A1200 060 | A500
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Re: New (to me) A3000

Postby danielj » Fri Feb 10, 2017 3:17 pm

=D>

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Re: New (to me) A3000

Postby trixster » Fri Feb 10, 2017 3:29 pm

I find it interesting that the composite output of Zarch on the A3000 is nearly full screen yet the lcdgamemodes adapted output of Zarch on my vga A3020 is a bit more squashed.

IMG_3975.JPG


The A3020 is smoother too but I guess that's the faster processor for you!

No joy with reseating the ram upgrade multiple times, I just get the floppy light giving out the error code and no boot.
A3020 | A3000 | A420/1 | BBC B + 128K RAM/ROM + 20K Shadow + Pi0 + VideoNuLA
Master Turbo + DC + BeebSID | Atom | A4000 060 | A3000 060 | A1200 060 | A500
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Re: New (to me) A3000

Postby daveejhitchins » Sat Feb 11, 2017 8:38 am

trixster wrote:It could be better but I think that's the best I can do.
I think it would be useful to use an old toothbrush to get rid of the 'blue/green'(?) that's visible between some of the IC legs - and, perhaps, flood the area with vinegar to ensure under the ICs are treated.

Dave H :D
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Re: New (to me) A3000

Postby trixster » Sat Feb 11, 2017 8:57 am

Good idea, I'll do that before I put the new battery in.
A3020 | A3000 | A420/1 | BBC B + 128K RAM/ROM + 20K Shadow + Pi0 + VideoNuLA
Master Turbo + DC + BeebSID | Atom | A4000 060 | A3000 060 | A1200 060 | A500
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Re: New (to me) A3000

Postby 1024MAK » Sat Feb 11, 2017 9:52 am

Then wash the crud away with clean water. Lots of water.
If you live in a hard water area, the final wash should be with de-ionised water (as used for topping up lead acid batteries).

Leave the PCB at a 60 to 70 degree angle in warm place for at least 24 hours so that any remaining water can evaporate.

While cleaning, check and clean any connectors / pins that may have been affected by contamination or corrosion.

Mark
For a "Complete BBC Games Archive" visit www.bbcmicro.co.uk NOW!
BeebWiki‬ - for answers to many questions...

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Re: New (to me) A3000

Postby trixster » Sat Feb 11, 2017 9:59 am

Thanks for the tips chaps! I'll reattack it midweek!

It makes me think I should have done a little more work on my A3020, although there was very little contamination on that compared to this one.
A3020 | A3000 | A420/1 | BBC B + 128K RAM/ROM + 20K Shadow + Pi0 + VideoNuLA
Master Turbo + DC + BeebSID | Atom | A4000 060 | A3000 060 | A1200 060 | A500
Atari Falcon 060 | Saturn | PS1 | SNES | CPC6128 | C64 | 3DO | MD | Jaguar

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Re: New (to me) A3000

Postby mw0uzo » Sat Feb 11, 2017 10:06 am

=D> =D> =D>
Excellent!!! That really cleaned up well with the vinegar.

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Re: New (to me) A3000

Postby trixster » Sat Feb 11, 2017 10:42 am

Does the ram expansion require a correctly operating cmos to work?
A3020 | A3000 | A420/1 | BBC B + 128K RAM/ROM + 20K Shadow + Pi0 + VideoNuLA
Master Turbo + DC + BeebSID | Atom | A4000 060 | A3000 060 | A1200 060 | A500
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Re: New (to me) A3000

Postby paulv » Sun Feb 12, 2017 9:29 pm

trixster wrote:I find it interesting that the composite output of Zarch on the A3000 is nearly full screen yet the lcdgamemodes adapted output of Zarch on my vga A3020 is a bit more squashed.

IMG_3975.JPG

The A3020 is smoother too but I guess that's the faster processor for you!

No joy with reseating the ram upgrade multiple times, I just get the floppy light giving out the error code and no boot.


You only need LCDGameModes if your monitor type is set to VGA or SVGA.

Is your A3020 set to MonitorType 4 and your A3000 set to monitor type 0?

If so, LCDGameModes will be altering the output on the A3020 to make Zarch output on a 31.5kHz display and this is where the aspect ratio can get a little out of whack. You need to alter your monitors settings through its own menu system to adjust the display so that it's more square.

On the composite output of the A3000, you're just outputting a standard 15kHz TV signal so, as long as the monitor can handle that rate, it should have the correct aspect ratio.

As for speed/smoothness, the A3000 is running at 8MHz, the A3020 at 12MHz so yes, the faster processor makes quite a difference. On an ARM3 it's a really smooth beautiful fast paced game :D

Paul

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Re: New (to me) A3000

Postby trixster » Mon Feb 13, 2017 8:42 am

Thanks for the reply Paul.

I'm pretty sure the A3020 is setup as svga, will check this evening. I'm sure that Lcdgamemodes is working correctly, I think the issue is with the dell 2001fp monitor I'm using - it's a great monitor as it'll work with a wide range of old kit and has a useful array of inputs but it's not great when it comes to adjusting an image. I don't think I can stretch the picture vertically when using VGA. That said, the dell is better than my viewsonic which is really letterboxed with the a3020 even when Lcdgamemodes is in use!
A3020 | A3000 | A420/1 | BBC B + 128K RAM/ROM + 20K Shadow + Pi0 + VideoNuLA
Master Turbo + DC + BeebSID | Atom | A4000 060 | A3000 060 | A1200 060 | A500
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Re: New (to me) A3000

Postby trixster » Mon Feb 13, 2017 7:03 pm

I've checked the a3020 and its running svga. However I think I've found the solution. The 2001fp won't allow me to stretch the vertical but I can use the zoom function. This makes the picture pretty much full screen - there's no clipping at the edges and the vertical is pretty much top to bottom. It works well.

Now annoyingly the a3000 will not sync with the 2001fp. I'm not sure why as it works fine with an Atari st and an Amiga 500 with rgb. Ive tried changing links 24 and 25. Itdoes work though with the gbs8200 that I use for my Beeb. One switch box later and I've got a useable setup until the autovidc is available again for purchase!

This is how they look - A3020 left with zoomed lcdgamemodes, A3000 on the right with vga going via gbs8200 (and a spot of Atari Falcon Doom in the middle!)

IMG_4001.JPG
A3020 | A3000 | A420/1 | BBC B + 128K RAM/ROM + 20K Shadow + Pi0 + VideoNuLA
Master Turbo + DC + BeebSID | Atom | A4000 060 | A3000 060 | A1200 060 | A500
Atari Falcon 060 | Saturn | PS1 | SNES | CPC6128 | C64 | 3DO | MD | Jaguar

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Re: New (to me) A3000

Postby trixster » Tue Feb 14, 2017 2:24 pm

Actually, I was completely wrong about the dell 2001fp not being able to support the A3000s video output, it works perfectly! I hadn't thought to hold down '4' whilst booting to enable SVGA rather than auto select.

IMG_4002.JPG


However... even with lcdgamemodes running the A3000 will not display Zarch on the monitor.
A3020 | A3000 | A420/1 | BBC B + 128K RAM/ROM + 20K Shadow + Pi0 + VideoNuLA
Master Turbo + DC + BeebSID | Atom | A4000 060 | A3000 060 | A1200 060 | A500
Atari Falcon 060 | Saturn | PS1 | SNES | CPC6128 | C64 | 3DO | MD | Jaguar

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Re: New (to me) A3000

Postby paulv » Tue Feb 14, 2017 11:03 pm

trixster wrote:However... even with lcdgamemodes running the A3000 will not display Zarch on the monitor.


At the desktop, change to mode 15 or 12, something that would be normally 15kHz and let it letterbox. Then launch Zarch.

Zarch has a hard time running when launching from VGA modes. Given it was written when Arthur was the primary OS for the Arc I guess it's not surprising that it has some issues.

EDIT: Also, as the screenshot shows, you're not running true VGA screen refresh rates which is what the VIDC Enhancer fixes.. I suppose I better pull my finger out and get well enough to be able to sit for long enough to build a few boards.

Paul

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Re: New (to me) A3000

Postby sirbod » Wed Feb 15, 2017 5:38 am

Does MODE 13 produce a display in BASIC? It should work on both VGA (type 3) and SVGA (type 4). If not, try altering the Sync setting.

Zarch doesn't touch VIDC, so should work on just about any VGA/SVGA capable LCD, provided the machine supports them - which it does in your case. You shouldn't need LCDGameModes for it either, it's only really required for overscan modes, or to correct the aspect ratio of non VGA/SVGA modes.

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Re: New (to me) A3000

Postby trixster » Wed Feb 15, 2017 10:37 am

Thanks for the replies gents.

I was about to ask about the sync settings. From the riscos site:

"This can generate separate syncs but requires links to be set to determine the polarity. It has only a 24Mhz crystal and can therefore only drive 'forgiving' monitors correctly that don't mind the 640x480 video mode timings being slightly incorrect.
The links to change, to set the sync polarity, are as follows:
Link 24: Change from SOUTH to NORTH
Link 25: Change from OPEN to CLOSED"

The LCD works ok for 640x480@57hz with Link 24 and 25 unchanged from South and Open. Should I be using North and Closed?

I will try modes 12 13 and 15 this evening.
A3020 | A3000 | A420/1 | BBC B + 128K RAM/ROM + 20K Shadow + Pi0 + VideoNuLA
Master Turbo + DC + BeebSID | Atom | A4000 060 | A3000 060 | A1200 060 | A500
Atari Falcon 060 | Saturn | PS1 | SNES | CPC6128 | C64 | 3DO | MD | Jaguar

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Re: New (to me) A3000

Postby paulv » Wed Feb 15, 2017 12:21 pm

Here are a few documents that may be of interest

The full Acorn video spec document for the A3000 and later machines

http://www.retro-kit.co.uk/user/custom/Acorn/32bit/documentation/Acorn_A3xA4xVideoSpec.pdf

... a useful Acorn doc about monitor connections for different machines

http://www.retro-kit.co.uk/user/custom/Acorn/Monitors/Acorn-AppNote-249.pdf

and in the appendices of the Ultra VIDC Enhancer documentation, there's a lot of info about the refresh rates you achieve both with and without a VIDC enhancer with one or two extra clocks.

The jumper settings for using a VGA monitor are also detailed on page 13 (pdf actual page 17)

http://www.retro-kit.co.uk/user/custom/Acorn/3rdParty/RetroKit/VIDCEnhancer2/manuals/VIDC-Enhancer-manual-v2.pdf

EDIT: I also had a prototype PCB manufactured (run of 10) which I have still got to build up which should allow an A3000 to automatically switch the sync-polarity by removing the jumpers and routing them through the new board...

http://stardot.org.uk/forums/viewtopic.php?f=16&t=10566&start=30#p132922

Paul

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Re: New (to me) A3000

Postby hubersn » Wed Feb 15, 2017 1:40 pm

trixster wrote:I was about to ask about the sync settings.


Don't forget to do a
*configure sync 0
for seperate sync.

I think it is not sufficient to just change the jumpers.

Have fun
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Re: New (to me) A3000

Postby trixster » Wed Feb 15, 2017 5:13 pm

Thanks again for all the info chaps! I'll read all those links!

I did another clean of the board and used a toothbrush to get under the sockets and ICs. Once dry I soldered in a new battery. My soldering skills are pants and weren't helped by the mess the old battery had made of the pads. I cleaned them up as best I could and eventually
managed to get the battery on.

It's worked, the power is on and the battery is now charging.
A3020 | A3000 | A420/1 | BBC B + 128K RAM/ROM + 20K Shadow + Pi0 + VideoNuLA
Master Turbo + DC + BeebSID | Atom | A4000 060 | A3000 060 | A1200 060 | A500
Atari Falcon 060 | Saturn | PS1 | SNES | CPC6128 | C64 | 3DO | MD | Jaguar

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Re: New (to me) A3000

Postby daveejhitchins » Wed Feb 15, 2017 7:10 pm

trixster wrote:My soldering skills are pants and weren't helped by the mess the old battery had made of the pads. I cleaned them up as best I could and eventually managed to get the battery on.
I shouldn't worry too much about your soldering skills when trying to solder on to pads that have been contaminated with battery leak . . . The solder is physically altered by the battery goo and everyone has problems! For future reference, a liberal dose of flux makes it a little easier.

Dave H :D
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Re: New (to me) A3000

Postby trixster » Wed Feb 15, 2017 8:37 pm

paulv wrote:
trixster wrote:However... even with lcdgamemodes running the A3000 will not display Zarch on the monitor.


At the desktop, change to mode 15 or 12, something that would be normally 15kHz and let it letterbox. Then launch Zarch.

Zarch has a hard time running when launching from VGA modes. Given it was written when Arthur was the primary OS for the Arc I guess it's not surprising that it has some issues.

EDIT: Also, as the screenshot shows, you're not running true VGA screen refresh rates which is what the VIDC Enhancer fixes.. I suppose I better pull my finger out and get well enough to be able to sit for long enough to build a few boards.

Paul


Right, the monitor will display modes 13 and 15 correctly, letterboxed as we would expect.

I've actually realised that from a on/off boot into the desktop (mode 27), if i run Zarch it displays correctly, letterboxed. It's only if I run lcdgamemodes first that Zarch fails to display correctly. So lcdgamemodes is stopping the A3000 displaying on the monitor.

On my A3020 lcdgamemodes works correctly and corrects the letterboxing into the 4:3 ratio we want.

So lcdgamemodes does not work with my A3000/monitor combination.
A3020 | A3000 | A420/1 | BBC B + 128K RAM/ROM + 20K Shadow + Pi0 + VideoNuLA
Master Turbo + DC + BeebSID | Atom | A4000 060 | A3000 060 | A1200 060 | A500
Atari Falcon 060 | Saturn | PS1 | SNES | CPC6128 | C64 | 3DO | MD | Jaguar

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Re: New (to me) A3000

Postby trixster » Wed Feb 15, 2017 8:48 pm

I still can't get the 4mb expansion to work, so I've ordered a £10 1mb expansion off evilbay to see if the problem lies with the a3000 or the 4mb board.
A3020 | A3000 | A420/1 | BBC B + 128K RAM/ROM + 20K Shadow + Pi0 + VideoNuLA
Master Turbo + DC + BeebSID | Atom | A4000 060 | A3000 060 | A1200 060 | A500
Atari Falcon 060 | Saturn | PS1 | SNES | CPC6128 | C64 | 3DO | MD | Jaguar

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Re: New (to me) A3000

Postby trixster » Wed Feb 15, 2017 8:59 pm

On closer inspection of the 4mb board, do I need to solder a link to get it working!? Is that what it's missing?

IMG_4007.JPG
A3020 | A3000 | A420/1 | BBC B + 128K RAM/ROM + 20K Shadow + Pi0 + VideoNuLA
Master Turbo + DC + BeebSID | Atom | A4000 060 | A3000 060 | A1200 060 | A500
Atari Falcon 060 | Saturn | PS1 | SNES | CPC6128 | C64 | 3DO | MD | Jaguar

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Re: New (to me) A3000

Postby dp11 » Wed Feb 15, 2017 9:15 pm

No. If you look carefully you can see it has already been done. :)

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Re: New (to me) A3000

Postby trixster » Wed Feb 15, 2017 9:19 pm

Ah, I see!
A3020 | A3000 | A420/1 | BBC B + 128K RAM/ROM + 20K Shadow + Pi0 + VideoNuLA
Master Turbo + DC + BeebSID | Atom | A4000 060 | A3000 060 | A1200 060 | A500
Atari Falcon 060 | Saturn | PS1 | SNES | CPC6128 | C64 | 3DO | MD | Jaguar

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Re: New (to me) A3000

Postby trixster » Sat Feb 18, 2017 11:05 am

The 1mb upgrade arrived, was installed and works perfectly.

IMG_4009.JPG


So I guess the 4mb board is faulty
A3020 | A3000 | A420/1 | BBC B + 128K RAM/ROM + 20K Shadow + Pi0 + VideoNuLA
Master Turbo + DC + BeebSID | Atom | A4000 060 | A3000 060 | A1200 060 | A500
Atari Falcon 060 | Saturn | PS1 | SNES | CPC6128 | C64 | 3DO | MD | Jaguar