Can all registered uses please login, even just for a few minutes..
It helps build a picture where our "good traffic" is coming from..
Thanks :)

A500 - resurrection or pit of despair?

Blogs & guides and tales of woo by forum members.
User avatar
JezC
Posts: 2819
Joined: Mon Aug 28, 2017 11:44 pm

Re: A500 - resurrection or pit of despair?

Post by JezC »

rubber_jonnie wrote: Sat Mar 15, 2025 3:13 pm
JezC wrote: Sat Mar 15, 2025 3:09 pm They were out of stock when I last looked...
Ahh, rubbish...
And they appear to be out of production on the website too... :cry:
User avatar
rubber_jonnie
Site Admin
Site Admin
Posts: 15066
Joined: Thu Aug 17, 2017 7:40 pm
Location: Essex
Contact:

Re: A500 - resurrection or pit of despair?

Post by rubber_jonnie »

JezC wrote: Sat Mar 15, 2025 10:10 pm
rubber_jonnie wrote: Sat Mar 15, 2025 3:13 pm

Ahh, rubbish...
And they appear to be out of production on the website too... :cry:
Ahh damn, they're very useful, I was thinking about getting some more.
Collector of many retro things!
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
Maximilian
Posts: 407
Joined: Thu Feb 28, 2019 5:02 pm

Re: A500 - resurrection or pit of despair?

Post by Maximilian »

JezC wrote: Thu Mar 13, 2025 8:33 pm The Rev 6 had an 8371 installed, swapped for a 8375 and away it went. Pretty sure it was the Rev 6.
There are different versions of the 8375, and only a few are pin compatible...
Seeing the rarity of an 8375 with the old pinout (<REV6) it could have been a Rev 8 board.

All A500 boards are called Rock lobsters, just refer to them by the revision.(A500 rev 6)

Please do not populate the empty memory on the Rev6 and higher boards, it will keep you from using specific expansions that use the trapdoor expansion slot.
Thinking of KCS Power PC boards, 1.8MB memory expansions(with Gary adapter), and some more exotic cards.
User avatar
rubber_jonnie
Site Admin
Site Admin
Posts: 15066
Joined: Thu Aug 17, 2017 7:40 pm
Location: Essex
Contact:

Re: A500 - resurrection or pit of despair?

Post by rubber_jonnie »

JezC wrote: Sat Mar 15, 2025 10:10 pm
rubber_jonnie wrote: Sat Mar 15, 2025 3:13 pm

Ahh, rubbish...
And they appear to be out of production on the website too... :cry:
Just a thought, did you try to email Chris? @cmorley are you still about on here? Is the 27C400 emulator still available?
Collector of many retro things!
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
User avatar
stephen_usher
Site sponsor
Site sponsor
Posts: 7464
Joined: Mon Nov 13, 2017 7:19 pm
Location: Oxford, UK.
Contact:

Re: A500 - resurrection or pit of despair?

Post by stephen_usher »

Maximilian wrote: Sun Mar 16, 2025 12:50 am Please do not populate the empty memory on the Rev6 and higher boards, it will keep you from using specific expansions that use the trapdoor expansion slot.
Thinking of KCS Power PC boards, 1.8MB memory expansions(with Gary adapter), and some more exotic cards.
Surely this is a balance between what you want to do with the machine? If you have no interest in those unusual boards then there's no down side and you get more chip RAM.
Intro retro computers since before they were retro...
ZX81->Spectrum->Memotech MTX->Sinclair QL->520STM->BBC Micro->TT030->PCs & Sun Workstations.
Added code to the MiNT kernel (still there the last time I checked) + put together MiNTOS.
Collection now with added Macs, Amigas, Suns and Acorns.
User avatar
rubber_jonnie
Site Admin
Site Admin
Posts: 15066
Joined: Thu Aug 17, 2017 7:40 pm
Location: Essex
Contact:

Re: A500 - resurrection or pit of despair?

Post by rubber_jonnie »

stephen_usher wrote: Sun Mar 16, 2025 9:57 am
Maximilian wrote: Sun Mar 16, 2025 12:50 am Please do not populate the empty memory on the Rev6 and higher boards, it will keep you from using specific expansions that use the trapdoor expansion slot.
Thinking of KCS Power PC boards, 1.8MB memory expansions(with Gary adapter), and some more exotic cards.
Surely this is a balance between what you want to do with the machine? If you have no interest in those unusual boards then there's no down side and you get more chip RAM.
I do agree. Also, how available are the exotics these days and at what price?

All I wanted for mine was 1MB RAM, but I could have done this with another 4 IC's on the board. Luckily I fixed my trapdoor card, but it could have easily gone either way, and I'm pretty happy with a total of 9MB RAM, 1MB chip, 8MB other on the A500 *MB + IDE upgrade.

Thinking of other upgrades, RGB2HDMI is definitely something I'm going to do with my A500, my A1200 already has DVI out.
Collector of many retro things!
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
cmorley
Posts: 296
Joined: Tue May 28, 2019 5:46 pm

Re: A500 - resurrection or pit of despair?

Post by cmorley »

rubber_jonnie wrote: Sun Mar 16, 2025 9:18 am Just a thought, did you try to email Chris? @cmorley are you still about on here? Is the 27C400 emulator still available?
Sadly not. I think all the chips are available again now after the chip shortage but I haven't made any more. I've not been very active in the retro community recently because of my day job :(

I might revisit it in the future but I'd need to make them even simpler to use to reduce the number of support requests I was getting.
User avatar
rubber_jonnie
Site Admin
Site Admin
Posts: 15066
Joined: Thu Aug 17, 2017 7:40 pm
Location: Essex
Contact:

Re: A500 - resurrection or pit of despair?

Post by rubber_jonnie »

cmorley wrote: Sun Mar 16, 2025 1:58 pm
rubber_jonnie wrote: Sun Mar 16, 2025 9:18 am Just a thought, did you try to email Chris? @cmorley are you still about on here? Is the 27C400 emulator still available?
Sadly not. I think all the chips are available again now after the chip shortage but I haven't made any more. I've not been very active in the retro community recently because of my day job :(

I might revisit it in the future but I'd need to make them even simpler to use to reduce the number of support requests I was getting.
Yeah, understand your decision 100%. They are a great item though, I haven't used mine a huge amount until my Amiga stuff lately, but I'm very happy with what they can do.
Collector of many retro things!
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
User avatar
JezC
Posts: 2819
Joined: Mon Aug 28, 2017 11:44 pm

Re: A500 - resurrection or pit of despair?

Post by JezC »

Ok, looked at the board & it says it's a 6A - it has the spare IC positions for an on-board upgrade to 1MB but I do have a couple of working 0.5 Meg trapdoor expansions that I could use, so the advice about limitations/compatibility issues of the different upgrade options is most welcome.

I'll try to see if the flash codes give me any hints (hopefully this evening) and report back with any progress when I have it.

Thanks all.

@cmorley if you do plan any future runs of those devices, I'd be interested, possibly in 2 or 3 at least but in the meantime I'll keep my eyes out for other options.

:thumbup:
Maximilian
Posts: 407
Joined: Thu Feb 28, 2019 5:02 pm

Re: A500 - resurrection or pit of despair?

Post by Maximilian »

rubber_jonnie wrote: Sun Mar 16, 2025 1:49 pm I do agree. Also, how available are the exotics these days and at what price?
There are recreations of the 1.8MB memory cards and you can use some with the CHIP mod giving you 1MB of chip and 1.3/1.5 slow/ranger men.
It is a cost effective way to get both kinds of memory(for game combability) and it leaves your CPU slot and side slot open for other expansions like the Action Replay.

The standard 0.5MB trapdoor expansions are dirt cheap and for a little more you get the 1.8MB version..

If you find a REV.8 board it is a totally different matter, it can hold 1MB chip on board (not always populated) and 1MB in the trapdoor for 2MB of chip.
Post Reply

Return to “MEMBER BLOGS”