Atom upgrades pt 2

discussion of games, software, hardware & emulators relating to the Acorn Atom and Acorn System machines.
Prime
Posts: 2784
Joined: Sun May 31, 2009 11:52 pm
Contact:

Atom upgrades pt 2

Post by Prime » Mon Sep 06, 2010 7:51 am

IMG_1774 - cropped.JPG
Atom colour board and video ram
IMG_1774 - cropped.JPG (469.15 KiB) Viewed 2649 times
Ok the board on the left is the first attempt at the colour board (note I only finished assembling it last night I have not yet had time to test it !).

On the right is a replacement video ram board, this replaces the 12 power hungry 2114s with a single less power hungry 6264 (this one was actually salvaged from a faulty electron upgrade board - thanks Dave :) ). The three wires you can see from this board don't plug into the video board but plug into the 74LS138 socket, which is under the video baord.

Cheers.

Phill.

User avatar
sirmorris
Posts: 773
Joined: Wed Feb 11, 2009 12:18 pm
Location: oxfordshire uk
Contact:

Re: Atom upgrades pt 2

Post by sirmorris » Mon Sep 06, 2010 8:34 am

It's worth saying that if you use proper board stackers then the upgrade is 100% reversible - it plugs into the existing sockets. Using pin headers might stretch the socket and then the RAM will be even more likely to fall out :roll:

I've soldered mine in :D I am of the opinion that an Atom is for modifying for life, not just for Christmas :lol:

Prime
Posts: 2784
Joined: Sun May 31, 2009 11:52 pm
Contact:

Re: Atom upgrades pt 2

Post by Prime » Mon Sep 06, 2010 8:39 am

sirmorris wrote:It's worth saying that if you use proper board stackers then the upgrade is 100% reversible - it plugs into the existing sockets. Using pin headers might stretch the socket and then the RAM will be even more likely to fall out :roll:
They ARE proper board stackers thes things https://www.rapidonline.com/productinfo ... ef=22-1704 to be precise :) :) :)

But yes using the 0.65" square pinheaders is not to be reccomended if plugging into scokets, plus they won't plug into turned pin sockets either.
I've soldered mine in :D I am of the opinion that an Atom is for modifying for life, not just for Christmas :lol:
Well at least that won't come free or fall out then :) :)

Phill.

Prime
Posts: 2784
Joined: Sun May 31, 2009 11:52 pm
Contact:

Re: Atom upgrades pt 2

Post by Prime » Mon Sep 06, 2010 6:11 pm

Woohoo, it works !!! Atom in colour, now to design the combined board that sirmorris wanted :)

Cheers.

Phill.

User avatar
sirmorris
Posts: 773
Joined: Wed Feb 11, 2009 12:18 pm
Location: oxfordshire uk
Contact:

Re: Atom upgrades pt 2

Post by sirmorris » Mon Sep 06, 2010 8:09 pm

=D> =D> You sir are a genius and I for one salute you! =D> =D>

Oh yes - one more for the 'ol girl:-
DSCF3947.JPG
SMB's version
DSCF3947.JPG (238.59 KiB) Viewed 2569 times

User avatar
iomanoid
Posts: 501
Joined: Sat Aug 08, 2009 9:38 am
Location: Baseworld: Cygni
Contact:

Re: Atom upgrades pt 2

Post by iomanoid » Mon Sep 06, 2010 8:11 pm

This is awesome, it's like some kind of strange porn that one simply doesn't fathom... like those ones with balloons or tentacles and that... :D
Image

Prime
Posts: 2784
Joined: Sun May 31, 2009 11:52 pm
Contact:

Re: Atom upgrades pt 2

Post by Prime » Mon Sep 06, 2010 10:43 pm

sirmorris wrote:=D> =D> You sir are a genius and I for one salute you! =D> =D>

Oh yes - one more for the 'ol girl:-
Excelent !

Glad you got it working, one down, two to go :)

BTW what isthe socket next to the video connector and the little bit of stripboard with the transistor on it ?

Cheers.

Phill.

User avatar
sirmorris
Posts: 773
Joined: Wed Feb 11, 2009 12:18 pm
Location: oxfordshire uk
Contact:

Re: Atom upgrades pt 2

Post by sirmorris » Tue Sep 07, 2010 6:16 am

Video level booster I think - there's a similar circuit found on most of my zeddies.

The socket is a 3.5mm jack for the video out. Not my addition.

I re-routed the video to the centre pole of the modulator last night so I have composite coming from the aerial socket. Sweet!

So how many mods is that now for this Atom ..

8th bit for printer port
ramrom expansion
video ram replacement
video re-route
video boost
:wink:

station240
Posts: 864
Joined: Tue Feb 09, 2010 6:11 pm
Location: South Australia
Contact:

Re: Atom upgrades pt 2

Post by station240 » Wed Sep 15, 2010 12:11 pm

Prime wrote:
sirmorris wrote:It's worth saying that if you use proper board stackers then the upgrade is 100% reversible - it plugs into the existing sockets. Using pin headers might stretch the socket and then the RAM will be even more likely to fall out :roll:
They ARE proper board stackers these things https://www.rapidonline.com/productinfo ... ef=22-1704 to be precise :) :) :)
I found some of these (well look the same in the pic), and they fit rather loosely in the machine pin IC sockets I use. The shop sell both so I was able to compare. I think the problem is the sockets are 0.6mm diameter, but the header pins are 0.3mm.

Its all rather annoying, only option left for me is some tinned copper wire or some suitable brass rod that has been tinned.

Prime
Posts: 2784
Joined: Sun May 31, 2009 11:52 pm
Contact:

Re: Atom upgrades pt 2

Post by Prime » Wed Sep 15, 2010 12:43 pm

station240 wrote:
Prime wrote: They ARE proper board stackers these things https://www.rapidonline.com/productinfo ... ef=22-1704 to be precise :) :) :)
I found some of these (well look the same in the pic), and they fit rather loosely in the machine pin IC sockets I use. The shop sell both so I was able to compare. I think the problem is the sockets are 0.6mm diameter, but the header pins are 0.3mm.
Well acording to the linked datasheet the pins on those are 0.47mm, and I have to say that they fit well in turned pin sockets, even better than they fit in the dodgy sockets that acorn used......

Cheers.

Phill.

station240
Posts: 864
Joined: Tue Feb 09, 2010 6:11 pm
Location: South Australia
Contact:

Re: Atom upgrades pt 2

Post by station240 » Wed Sep 15, 2010 2:56 pm

Ok thanks.

I've got three 6264's here, untested but two are unused. You can have them for a small amount plus postage.

Prime
Posts: 2784
Joined: Sun May 31, 2009 11:52 pm
Contact:

Re: Atom upgrades pt 2

Post by Prime » Wed Sep 15, 2010 3:05 pm

Thinking about it I wonder if I should design the video / ram board to also be able to use a 16K or 32K ram (as these might be more common), obviously grounding the upper address lines. Now if the ROM-RAM board's CPLD had a couple of spare lines (which it doesn't), I could have controlled them with it.....maybe that's for ver 1.5 :)

Also wonder if I should also adapt to being able to take a skinny-dip, as the rom-ram board can, as I have a truck load of those thanks to old [3,4,5]86 boards.....

Cheers.

Phill.

User avatar
sirmorris
Posts: 773
Joined: Wed Feb 11, 2009 12:18 pm
Location: oxfordshire uk
Contact:

Re: Atom upgrades pt 2

Post by sirmorris » Wed Sep 15, 2010 4:29 pm

+1 for skinny dips.
+1 for 'wasting' the unused address lines.

Forget about video ram paging, once the inevitable 4-frame porn animation had been implemented then there'd be no other use ;)

Prime
Posts: 2784
Joined: Sun May 31, 2009 11:52 pm
Contact:

Re: Atom upgrades pt 2

Post by Prime » Wed Sep 15, 2010 8:30 pm

sirmorris wrote:+1 for skinny dips.
+1 for 'wasting' the unused address lines.
Right will add that to the board, asuming that the current prototype works once I've finished drilling and soldering it, I should be ready to get some boards made, if people are interested....
Forget about video ram paging, once the inevitable 4-frame porn animation had been implemented then there'd be no other use ;)
:) PigROM-Atom anyone ? :) :)

Well the vidram paging was just an idle thought if using a 32K ram, seems a shame to waste 3/4 of it :) :)

Cheers.

Phill.

User avatar
sirmorris
Posts: 773
Joined: Wed Feb 11, 2009 12:18 pm
Location: oxfordshire uk
Contact:

Re: Atom upgrades pt 2

Post by sirmorris » Wed Sep 15, 2010 9:00 pm

You could just leave the spare lines pulled down and have a couple of pads..

The AtomMMC has a couple of spare IO lines ;)

User avatar
retroclinic
Posts: 3032
Joined: Thu Jul 03, 2008 1:22 pm
Location: East Riding of Yorkshire
Contact:

Re: Atom upgrades pt 2

Post by retroclinic » Wed Sep 15, 2010 9:02 pm

You could use a 1 MB ram chip, then you'd get 128 frames of 8k each, or 5.12 seconds of FMV @ 25FPS.....PigROM in HD :shock:

Good work on all this Phill, I've been reading with interest, I'm just not as "into" the Atom.

Mark.
Image

Prime
Posts: 2784
Joined: Sun May 31, 2009 11:52 pm
Contact:

Re: Atom upgrades pt 2

Post by Prime » Wed Sep 15, 2010 9:47 pm

sirmorris wrote:You could just leave the spare lines pulled down and have a couple of pads..

The AtomMMC has a couple of spare IO lines ;)
That might be an idea actually have a 2 pin jumper on each of the top two address lines that closed grounds them, but if you want to control them externally, remove the jumper and connect to the pad/pin.

Cheers.

Phill.

Prime
Posts: 2784
Joined: Sun May 31, 2009 11:52 pm
Contact:

Re: Atom upgrades pt 2

Post by Prime » Wed Sep 15, 2010 9:51 pm

retroclinic wrote:You could use a 1 MB ram chip, then you'd get 128 frames of 8k each, or 5.12 seconds of FMV @ 25FPS.....PigROM in HD :shock:
I actually have a couple of those that I bought a while back, though they are surface mount tho..... mind so's the video converter :)
Good work on all this Phill, I've been reading with interest, I'm just not as "into" the Atom.
Cheers :)

Yeah well you can't be interested in every machine :) though it's not that I'm not into the other Acorn 8 bits, just at the mo the Atom is my focus, as I guess it's easy to improove :) :)

Humm wonder if I could hack Atom dos to talk to the datacentre.......

Cheers.

Phill.

User avatar
ukretrogamer
Posts: 432
Joined: Mon Nov 09, 2009 8:55 pm
Location: England's largest town
Contact:

Re: Atom upgrades pt 2

Post by ukretrogamer » Wed Sep 15, 2010 11:17 pm

Prime wrote:Humm wonder if I could hack Atom dos to talk to the datacentre.......
Now *THAT* would be nice. A potential waste of gigabytes of storage capacity but nice, all the same! (And it'd probably require a VIA, which I don't have) :cry:

Prime
Posts: 2784
Joined: Sun May 31, 2009 11:52 pm
Contact:

Re: Atom upgrades pt 2

Post by Prime » Thu Sep 16, 2010 12:09 am

ukretrogamer wrote:
Prime wrote:Humm wonder if I could hack Atom dos to talk to the datacentre.......
Now *THAT* would be nice. A potential waste of gigabytes of storage capacity but nice, all the same! (And it'd probably require a VIA, which I don't have) :cry:
You'll have a VIA soon :) I've assembled your ram-rom board, just got to get the CPLD and ROM programmed :)

If I where looking at interfacing the Datacentre, you'd prolly need to fake up the 1MHz bus from the beeb, esentially you'd just need to decode a couple of address lines and find it somewhere to sit in the Atom address map, in the Bxxx page perhaps ?

What you would need however is an external bus connector, and the bus interface chips 2 81LS95 and an 8304, which are pure unobtanium, though I believe you can shoehorn standard 74LS244/74LS245 chips in there.

Cheers.

Phill.

Prime
Posts: 2784
Joined: Sun May 31, 2009 11:52 pm
Contact:

Re: Atom upgrades pt 2

Post by Prime » Thu Sep 16, 2010 12:12 am

Ok here's the finalish version, I etched assembled and check this over the course of this evening which I don't think's bad going :) :)
IMG_1783 - cropped.JPG
Atom rom and colour combined board.
IMG_1783 - cropped.JPG (620.34 KiB) Viewed 2231 times
The only change after this has been to add the facility for 0.6" or 0.3" ram chips, and to take the two upper address lines to a 2x2 jumper block.

So hopefully it's off to the boardhouse in the next few days.....

Cheers.

Phill.

User avatar
ukretrogamer
Posts: 432
Joined: Mon Nov 09, 2009 8:55 pm
Location: England's largest town
Contact:

Re: Atom upgrades pt 2

Post by ukretrogamer » Tue Nov 30, 2010 10:21 am

Hi Phill

Any further developments to your colour board? I'd still like to get one of these to add to my Atom.

Regards
Mark

Prime
Posts: 2784
Joined: Sun May 31, 2009 11:52 pm
Contact:

Re: Atom upgrades pt 2

Post by Prime » Tue Nov 30, 2010 4:18 pm

ukretrogamer wrote:Hi Phill

Any further developments to your colour board? I'd still like to get one of these to add to my Atom.
Not had a chance to get the boards made yet, I have prety much everything else tho. There is one thing you should know, this board only works with a SCART compatible monitor or TV, as the video is output at 0.7Vptp. So it won't work on most CUBs which require TTL RGB.

It will work on the AKF-11 (I think that's the one, supplied with my compact), but only if you use the SCART input.

BTW did you still want one of the RAM/ROM boards, I think Charlie and I have worked out what the problem was he was having with his MMC interface in the same machine.

Cheers,

Phill.

User avatar
sirmorris
Posts: 773
Joined: Wed Feb 11, 2009 12:18 pm
Location: oxfordshire uk
Contact:

Re: Atom upgrades pt 2

Post by sirmorris » Tue Nov 30, 2010 4:26 pm

Phill - will the signals be present on a header in case one day some wizard comes along and makes a CUB adapter board?? Eh? Eh? [-o<

Prime
Posts: 2784
Joined: Sun May 31, 2009 11:52 pm
Contact:

Re: Atom upgrades pt 2

Post by Prime » Tue Nov 30, 2010 5:33 pm

sirmorris wrote:Phill - will the signals be present on a header in case one day some wizard comes along and makes a CUB adapter board?? Eh? Eh? [-o<
You notice that there are two 2x5 connectors, one connects to the 2x5 video connector on the main board to pick up the signals from the VDG, the other is the video output, it currently has (from memory, I'll check the schematic when I'm at home)

R,G,B : 0.7Vptp
Comp Sync : TTL
+5V
GND
Mono video (straight through from Atom).

I suppose I could route the seperate syncs to the output if that would help, should be easy enough to do, though IIRC the CUB requires comp sync anyways.
The comp sync can also have it's polarity reversed by way of a jumper, incase your monitor needs it.

Cheers,

Phill.

User avatar
ukretrogamer
Posts: 432
Joined: Mon Nov 09, 2009 8:55 pm
Location: England's largest town
Contact:

Re: Atom upgrades pt 2

Post by ukretrogamer » Tue Nov 30, 2010 6:33 pm

Prime wrote:It will work on the AKF-11 (I think that's the one, supplied with my compact), but only if you use the SCART input.
That's good news. That's exactly what I'm using as my primary monitor because it has a BBC domino and a SCART connector. Will it need a special cable?
Prime wrote:BTW did you still want one of the RAM/ROM boards, I think Charlie and I have worked out what the problem was he was having with his MMC interface in the same machine.
Oh heck, yes. ROM/RAM & Colour Card please?

User avatar
ukretrogamer
Posts: 432
Joined: Mon Nov 09, 2009 8:55 pm
Location: England's largest town
Contact:

Re: Atom upgrades pt 2

Post by ukretrogamer » Thu Jan 27, 2011 9:47 pm

Someone else seems to be selling Atom Colour cards over on the Retro Computer Museum Forums: http://retrocomputermuseum.co.uk/forum/ ... pic=3130.0

Any further news on yours Phill?

Prime
Posts: 2784
Joined: Sun May 31, 2009 11:52 pm
Contact:

Re: Atom upgrades pt 2

Post by Prime » Thu Jan 27, 2011 11:42 pm

ukretrogamer wrote:Someone else seems to be selling Atom Colour cards over on the Retro Computer Museum Forums: http://retrocomputermuseum.co.uk/forum/ ... pic=3130.0

Any further news on yours Phill?
Ahh, yes the Acorn design, I seem to remember it being a little hard to adjust properly, on the other hand it does output TTL RGB and colour composite. My design is SCART RGB only, but does have the replacement video RAM chip.

I will get to it and send them for production this weekend ! I promise.

Cheers.

Phill.

Prime
Posts: 2784
Joined: Sun May 31, 2009 11:52 pm
Contact:

Re: Atom upgrades pt 2

Post by Prime » Sun Jan 30, 2011 3:14 pm

Prime wrote: I will get to it and send them for production this weekend ! I promise.
Just to let you all know I hvae just uploaded the files to order 10 of my Colour boards on an 11 (working day) scedule, so should be with me in about a fortnight.

Just a reminder these ONLY output SCART level colour at 60Hz. But if you use the same monitor / TV for your Atom normally they should work.

Cheers.

Phill.

Prime
Posts: 2784
Joined: Sun May 31, 2009 11:52 pm
Contact:

Re: Atom upgrades pt 2

Post by Prime » Tue Feb 22, 2011 2:49 pm

Ok boards are here I'll be assembling one to test over the next couple of days will
post some piccies, contact ppl once that is done !

Cheers.

Phill.

Post Reply