New Saturn 128k compatible cards

8 posts / 0 new
Last post
Offline
Last seen: 8 hours 10 min ago
Joined: Aug 4 2018 - 21:59
New Saturn 128k compatible cards

I was reading a recent post about desirable cards and I noticed the Saturn 128k card was one that a number of people want.

Perfect timing because I have just completed the design for a reboot of the Saturn 128k memory card and they are much cheaper than current offerings I've seen.

I'm offering bare pcbs with gold plated edge connectors for US$10 plus $3.50 postage.
A download link for the GED files needed to program the GAL will be provided those that purchase a board.

PM me for my PayPal details if you want to order.

The cost of the parts I estimate to be less than $10.
3 x 74LS74
1 x KM681000BLP-5 or AS6C1008-55PCN Static RAM ( 128k x 8 ) (Any 32pin dip that is 5v tolerant should work)
1 x GAL22v10 or GAL20v8 or V750C
4 x 3mm LED
4 x 470R 1/6W resistor
1 x 47uF 16v electrolytic capacitor
5 x 0.1uF Monolithic ceramic capacitor
1 x 1n4148 signal diode

This is a prototype (no gold plating)

The rendering of the production boards

The prototype along side an original Saturn card

AttachmentSize
Image icon Saturn.jpg269.79 KB
Image icon saturn3.jpg122.25 KB
Image icon Saturn2.jpg172.16 KB
Offline
Last seen: 6 hours 27 min ago
Joined: May 22 2013 - 20:37
WOW! Congratulations. It

WOW! Congratulations. It looks nice!

Offline
Last seen: 16 hours 22 min ago
Joined: Jul 5 2018 - 09:44
Nice! I've got one of the

Nice! I've got one of the old Tiawan/Hong Kong made knock-offs of the Saturn 128. I've been working on some cards for the Apple II as well. What software do you use for laying out your PCBs? Do you have a place that will fab boards like this at a reasonable price? I've got several designs that are at the prototype stage but I'm struggling with moving to the next level. I have someone who has been helping me with board layout in Eagle for one of my designs but I hate to ask her to do more than she's already volunteered for. Also Lattice GAL22V10 are starting to become an issue to get since they've been out of production for a while now. I have a few, but not a lot. Atmel is making 22V10... but theirs has a funky programming algorithm and none of the inexpensive programmers including the MiniPro TL866CS that I have will handle them. And I'm not sure if the expensive programmer they recommend has Linux support, which if it doesn't means I can't use it since I don't have Windows or a Mac for that matter. Well, unless the software works under Wine.

Offline
Last seen: 8 hours 10 min ago
Joined: Aug 4 2018 - 21:59
softwarejanitor wrote:Nice!

softwarejanitor wrote:
Nice! I've got one of the old Tiawan/Hong Kong made knock-offs of the Saturn 128.

I have six of them, they keep dying and I got sick of repairing them.

softwarejanitor wrote:
What software do you use for laying out your PCBs?

I use KiCAD for schematic capture and pcb layout, Freerouter to autoroute the traces and then I manually tweak the traces back in KiCAD.

softwarejanitor wrote:
Do you have a place that will fab boards like this at a reasonable price?

I use JLPCB they are cheap but great quality. Fast as well, I submitted the artwork for the production boards Friday night and had them arrive 10am today (4 and half days including the weekend).

softwarejanitor wrote:
Also Lattice GAL22V10 are starting to become an issue to get since they've been out of production for a while now.

GAL22V10 are common and cheap on ebay ($1.50 or less). GAL20V8 if you have some lying around can also be used but they are more expensive on ebay. If you prefer you can also use the ATF750C, they are still in production. I provide JED files for all three chips so I'm confident finding a suitable GAL to assemble the board wont be a problem.

Offline
Last seen: 8 hours 10 min ago
Joined: Aug 4 2018 - 21:59
Ready to ship.

I now have the production boards in hand.
I assembled and tested one and it works flawlessly.

I've tested it in a 2e, a 48k clone, a 64k clone, a z80+64k clone and a Vectorio 64k with no issues.

For those that have already paid I'll be posting your boards this afternoon.

For those that haven't... PM me for my paypal details.

Edit: Add a Rev D Apple2+ (820-0044-D) to the list of machines I have tested the card in. (I repaired a faulty mainboard so i could test the card in it)

Offline
Last seen: 8 hours 10 min ago
Joined: Aug 4 2018 - 21:59
A lesson learned.

A lesson learned.

Never assume your universal programmer will support a device.
I just spent $20 for a couple of ATF750C cpld's to test only to discover the TL866 programmer doesnt support them, in fact none of the cheaper programmers do.

So when buying parts for the Saturn card, I suggest using a GAL22V10-7

Offline
Last seen: 16 hours 22 min ago
Joined: Jul 5 2018 - 09:44
Yeah, and you need a Lattice

Yeah, and you need a Lattice GAL22V10 which are unfortunately starting to get scarce as they are out of production since 2011. As I mentioned before, the readily available Atmel ATF22V10 uses a proprietary programming protocol and is also not supported by the TL866 or any of the other inexpensive programmers. You can still find the Lattice fabbed parts but they are starting to get harder to find and the price is starting to go up. Also I've been warned that there may be some counterfeit parts out there from some of the more fly-by-night Chinese suppliers. Whether those work at all or not, I can't say.

Offline
Last seen: 8 hours 10 min ago
Joined: Aug 4 2018 - 21:59
What the chinese are selling

What the chinese are selling are pulls from ewaste sent there for recycling.
If you are lucky half or more wont be DOA, so order extra's.

I just saw something promising.... the G540 universal programmer lists the Atmel ATF22V10C in its supported chip list.
I found the algorithm to program the chip and sent an email requesting support be included with a link to the algorithm to the people that make my TL866CS. Hopefully they add support but I might go order a G540 now.

Update: I heard back from an engineer, he says "It is being planned, but we do not have even an estimated release date for it."
Well i don't want to wait indefinitely so I decided on a VS4800, from the company that make the G540 but a more advanced model. Basically $150 damage with DHL shipping. But at least I will be able to use brand new GAL's when I sell fully assembled boards online.

Log in or register to post comments