My A3000 - work done so far (pics only)

[IanJeffray]

I think 8MB would be more than enough, but these expansions are like gold dust nowadays...

A 16MB RAM card would be finally easier to get (and cheaper).

I'm working on a smaller/cheaper 8MB for A3000 and other machines. Have patience. There's a large amount of "glue" on the 16MB board that's nominally (and empirically) not required for just a 'standard' master/slave 8MB MEMC arrangement. I already completed an A5000 8MB board design, but it uses the programmable logic parts from the Atomwide board design, which are PEELs, not PAL/GALs and can't be bit copied - and the recovered logic is a little illogical...

Anyway, 8MB is definitely the sweet spot for RISC OS 3.1 in my opinion. To use anything more you really have to be using the machine hard in desktop. The 4MB limit on RMA becomes the biggest limitation IMO ... that's one reason for my 4MB ROM carrier, so that we can eventually spin up a RISC OS with things like Internet and WIMP 3.9 etc in true ROM, saving RMA.

[Joka80]

A 16MB RAM card would be finally easier to get (and cheaper).

From where exactly?

[HigashiJun]

I'm working on a smaller/cheaper 8MB for A3000 and other machines.

Great news !

Looking forward to seeing this project turn out good.

[HigashiJun]

From where exactly?

I had in mind IanJeffray's 16MB expansion, which would be cheaper to build than buying (and finding) a 8MB expansion for the A3000.

[HigashiJun]

A good progress since my last post.

Finally did it !:

A User Port / Midi Port / Analogue port /Ethernet / IDE podule for my Archie 3000.

The IDE podule is not yet fitted at the back of this multi podule.

Everything is internal and the top lid closes perfectly.

I have to think where to place the BNC connector though...

[HigashiJun]

It's been a long time since my last post, but my work kept me quite busy (my soldering iron went also fubar and the replacement part took more than 2 weeks to reach me...).

The soldering station is now back on its feet and ready to assist me in my never-ending projects.

So here's a little digest on my past progress with my Archie A3000 project.

I found this little marvel on EvilBay:

and I decided to replace my previously installed BNC podule. Here's the result:

Short pins fitted !

Connectors for IDE podule ready

Looks good..

Will have to cut the plate for the RJ45 connector and the LED.

So far so good.


I then wanted to arrange the wires better:

This one went OK

but the other one had to ruin my day when a pin broke...


And of course, I didn't have any spares in my parts box and had to order some.

Now I have to wait, and meanwhile desolder the connector with its broken pin.

Nevertheless, I had another mod in my head whilst the soldering iron was still hot.

I have decided to give my Aleph One a little surgery.

Before:

After:

A socket is fitted under the oscillator and changing the ARM clock is now easy.

Once the podules are finished for good, I will try a 66Mhz crystal.

Everything fits nicely under the limited space under the keyboard, and works without any glitches at 30Mhz.



More to come soon.

[IanJeffray]

works without any glitches at 30Mhz.

My experience with overclocking ARM3s is that they don't "glitch" - they either work perfectly, or essentially not at all. YMMV.

[HigashiJun]

My experience with overclocking ARM3s is that they don't "glitch" - they either work perfectly, or essentially not at all. YMMV.

Good to know that !

So, according to your experience, I can say my ARM3 works perfectly at 30Mhz.

Let's see how it will work at 33Mhz then...

[a1exh]

Great job. I would love to find an ARM3 for my A310 but they are super expensive / hens teeth these days. Awesome job.

[HigashiJun]

Thank you @a1exh

You can still get an ARM3 upgrade for your A310 on Ebay, and for much cheaper than the price I paid for my Aleph One...

Or you can still build one provided you can source an ARM3 CPU.

Check the excellent IanJeffary's GitHub page:

https://github.com/IJeffray?tab=repositories

[HigashiJun]

The missing part finally arrived today, and I could almost finish the 3 in 1 podule mod:

Looks better with the pins going upward and the cable tie as a strain relief for the 3 wires...

The IDE podule will be fitted horizontally.

And here's what it will look like with the CF card installed.


Since the IDE podule collides with the plastic pole, I have to shorten the IDE podule pins and file this plastic pole a bit such it holds the IDE podule.

[IanS]

As you are modifying and soldering to podules, can you not fit the IDE podule under the bottom podule, attach it to the long pins of the lower podule. Seems like there is quite a void under there.

[HigashiJun]

You mean under the Morley Midi podule ?

It was a solution I had considered, but I have finally decided to have something I can easily dismantle and maintain in case of problems.

Having the IDE podule at the top is also convenient for accessing the CF card.

[HigashiJun]

Pins shortened and plastic pole filed:

The pole is a good strain relief for the IDE adapter.

I will test the CF card later as I plan to buy another CF to IDE adapter...

Next step is to cut off the metal plate for the RJ45 connector and drill a hole for the LED.

[HigashiJun]

And the opening for the RJ45 connector is done and the hole for the LED is drilled:

Could have done better (the Dremel and the drill left some scars) , but since I don't have a drill press nor vice for this kind of job, I cannot blame myself too much...

I have to file the inside of the upper lid at the RJ45 connector now to have it flat when closed:

More to come...

[HigashiJun]

And the upper lid is done:

and closed:

[HigashiJun]

And as expected, the CF card adapter I wanted to fit doesn't work:

so I have to use a standard one:

It's a pity as the first one was a perfect fit for my 3-in-1 podule.

I will have to connect the standard CF adapter via a 44 pin cable and probably attach it on the FDD...

[baz4096]

Could you have considered a flying lead with 8P8C socket/female rather than modifying your case?

[HigashiJun]

Could you have considered a flying lead with 8P8C socket/female rather than modifying your case?

Yes.

I bought one, but finally opted for the current solution.

I'm personally not fond of modifying cases, but it was the most viable solution for me.

[IanJeffray]

And the upper lid is done:

That is absolute tradgedy.

[HigashiJun]

That is absolute tradgedy.

I know...