Watford Electronics PALPROM Redesign

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hoglet
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Watford Electronics PALPROM Redesign

Post by hoglet » Wed Oct 24, 2018 6:48 pm

(Continued from RGBtoHDMI Thread)

Today, for a but of fun, I've been building my own Watford Electronics PALPROM carrier so I can play with IanB's wonderful Quest Paint program.

There now is a github repository for this project containing:
- KiCad 5 Schematic and PCB
- GAL16V8 design for Quest Paint
- Original ROM images
- Original disk images
- Documentation

The Quest Paint PAL re-design uses the same pinout at the original, but was re-created from scratch so it might have subtle differences.

Here's some photos...

The PCB layout printed out on drafting film:
IMG_1466.JPG
The PCB etched and drilled with 0.7mm holes:
IMG_1459.JPG
(only a couple of slightly wayward holes!)

All soldered up:
IMG_1463.JPG
(the flux will get cleaned off soon!)

GAL16V8 PAL installed and programmed:
IMG_1461.JPG
IMG_1462.JPG
(the jedec file is in gitub)

It's ended up a very similar form factor to Ian's original:
Quest.jpg
If you didn't want to socket the PAL, you could reduce the height a bit:
IMG_1464.JPG
Installed in my Master as ROM 8:
IMG_1465.JPG
And amazingly it worked first time:
IMG_1467.JPG
Ian, is there a manual online anywhere for Quest Paint?

Dave
Last edited by hoglet on Wed Oct 24, 2018 7:01 pm, edited 10 times in total.

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BigEd
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Re: Watford Electronics PALPROM Redesign

Post by BigEd » Wed Oct 24, 2018 6:59 pm

Amazing, and splendid!

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IanB
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Re: Watford Electronics PALPROM Redesign

Post by IanB » Wed Oct 24, 2018 10:18 pm

hoglet wrote:
Wed Oct 24, 2018 6:48 pm
Ian, is there a manual online anywhere for Quest Paint?
I don't think anyone's scanned it but I have a copy and also a copy of the Wapping Editor manual as well so I'll scan them when I have time.
Meanwhile, here is the draft manual in View format:
Quest Paint Manual (View format).dsd
(400 KiB) Downloaded 31 times
You can view this as text in DFS explorer and it's more or less readable.

BTW Wapping Editor is essentially a Mode 0 version of Quest Paint with a text editor, font editor and typesetter.

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hoglet
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Re: Watford Electronics PALPROM Redesign

Post by hoglet » Wed Oct 24, 2018 10:29 pm

Again, many thanks.

How different is the carrier board for Wapping Editor?

It will need A15 on the 27C512 driving from the PAL. I wonder if that's the only difference.

Dave

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IanB
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Re: Watford Electronics PALPROM Redesign

Post by IanB » Thu Oct 25, 2018 12:59 am

hoglet wrote:
Wed Oct 24, 2018 10:29 pm
How different is the carrier board for Wapping Editor?
I'll trace the tracks when I have the time.

BTW the original boards had the PAL mounted upside down on the bottom of the pcb

I wonder if it would be possible to come up with a universal board and PLD that could cope with 32K and 64K and and switch between them with a link.
Last edited by IanB on Thu Oct 25, 2018 1:02 am, edited 1 time in total.

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Re: Watford Electronics PALPROM Redesign

Post by hoglet » Thu Oct 25, 2018 7:45 am

IanB wrote:
Thu Oct 25, 2018 12:59 am
I'll trace the tracks when I have the time.
Thanks.

I think it will be different. I would expect pin 6 would have been brought into use, freeing one output macrocell for the additional logic. I think 7 macrocells are needed for the 64K design, rather than the 6 used by the 32K design. I was going to write the PAL for that this morning to check.
IanB wrote:
Thu Oct 25, 2018 12:59 am
BTW the original boards had the PAL mounted upside down on the bottom of the pcb
Interesting and slightly surprising, as the pinout seems to have been optimised for top-mounting.

Could you take a couple of photos of the top and bottom of the Quest Paint board without the ROM and PAL fitted?
IanB wrote:
Thu Oct 25, 2018 12:59 am
I wonder if it would be possible to come up with a universal board and PLD that could cope with 32K and 64K and and switch between them with a link.
Yes it would, but I think you would need to move to a CPLD. This has the advantage of being lower profile, as well as being programmable insitu.

I do still like the idea of two-socket cartridge port version.

I wonder if anyone has a KiCad design for a ROM cartridge?

Dave
Last edited by hoglet on Thu Oct 25, 2018 7:46 am, edited 2 times in total.

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Re: Watford Electronics PALPROM Redesign

Post by daveejhitchins » Thu Oct 25, 2018 9:04 am

hoglet wrote:
Thu Oct 25, 2018 7:45 am
IanB wrote:
Thu Oct 25, 2018 12:59 am
I'll trace the tracks when I have the time.
Thanks.

I think it will be different. I would expect pin 6 would have been brought into use, freeing one output macrocell for the additional logic. I think 7 macrocells are needed for the 64K design, rather than the 6 used by the 32K design. I was going to write the PAL for that this morning to check.
IanB wrote:
Thu Oct 25, 2018 12:59 am
BTW the original boards had the PAL mounted upside down on the bottom of the pcb
Interesting and slightly surprising, as the pinout seems to have been optimised for top-mounting.

Could you take a couple of photos of the top and bottom of the Quest Paint board without the ROM and PAL fitted?
IanB wrote:
Thu Oct 25, 2018 12:59 am
I wonder if it would be possible to come up with a universal board and PLD that could cope with 32K and 64K and and switch between them with a link.
Yes it would, but I think you would need to move to a CPLD. This has the advantage of being lower profile, as well as being programmable insitu.

I do still like the idea of two-socket cartridge port version.

I wonder if anyone has a KiCad design for a ROM cartridge?

Dave
Dave, I can send you DXFs of a large and small cartridge PCB, when I get home this weekend, if they would help?

Any chance this would work on the Electron ??

Dave H :D

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hoglet
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Re: Watford Electronics PALPROM Redesign

Post by hoglet » Thu Oct 25, 2018 9:18 am

daveejhitchins wrote:
Thu Oct 25, 2018 9:04 am
Any chance this would work on the Electron ??
Yes please for the DFX files.

If by this you mean the Quest Paint program, I think not as it uses MODE 7 for some things.

Dave

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Re: Watford Electronics PALPROM Redesign

Post by hoglet » Thu Oct 25, 2018 12:52 pm

I've added a PLD file for Wapping Editor, currently untested:
https://github.com/hoglet67/palprom/tre ... ing_editor

It will need to be updated once Ian confirms the original PAL pinout.

Dave

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Re: Watford Electronics PALPROM Redesign

Post by daveejhitchins » Sun Oct 28, 2018 11:31 am

Here's what I've been using for my Cartridge PCBs. Attached is the Large PCB. If anyone would like me to adjust for the small PCB, just shout.

Dave H :D
Cartridge Case and Board.dxf.zip
(3.83 KiB) Downloaded 28 times

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Re: Watford Electronics PALPROM Redesign

Post by danielj » Sun Oct 28, 2018 12:07 pm

IanB wrote:
Wed Oct 24, 2018 10:18 pm

I don't think anyone's scanned it but I have a copy and also a copy of the Wapping Editor manual as well so I'll scan them when I have time.
I did scan the wapping editor manual and uploaded it to archive.org :)

https://archive.org/details/wedit_201511

d.

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Re: Watford Electronics PALPROM Redesign

Post by aotta » Sat Jul 18, 2020 6:19 pm

hoglet wrote:
Thu Oct 25, 2018 12:52 pm
I've added a PLD file for Wapping Editor, currently untested:
https://github.com/hoglet67/palprom/tre ... ing_editor

It will need to be updated once Ian confirms the original PAL pinout.

Dave
was the jed file tested? i used your files for Quest paint and it worked fine, but the wapping editor version stop my Master from booting.
I don't know if i missed something or the Wapping Editor version is still in progress...

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Re: Watford Electronics PALPROM Redesign

Post by IanB » Mon Jul 20, 2020 6:03 pm

aotta wrote:
Sat Jul 18, 2020 6:19 pm
was the jed file tested? i used your files for Quest paint and it worked fine, but the wapping editor version stop my Master from booting.
I don't know if i missed something or the Wapping Editor version is still in progress...
It hasn't been tested so it will need to be looked at when I have the time.

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Re: Watford Electronics PALPROM Redesign

Post by aotta » Mon Jul 20, 2020 6:17 pm

IanB wrote:
Mon Jul 20, 2020 6:03 pm
aotta wrote:
Sat Jul 18, 2020 6:19 pm
was the jed file tested? i used your files for Quest paint and it worked fine, but the wapping editor version stop my Master from booting.
I don't know if i missed something or the Wapping Editor version is still in progress...
It hasn't been tested so it will need to be looked at when I have the time.
Thank Ian for the answer, so i know it's not my fault in assembling it.

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