21 replies to this topic

[kamakazi]

Does anyone here know where I might could find that 7800 Devcard Kit without having to buy it in a package deal (with an ST)? I've tried Best Electronics, and he will not split them up...can't say that I blame him.

Help please!

[primeform]

kamakazi, on Tue Aug 19, 2008 9:03 PM, said:

Does anyone here know where I might could find that 7800 Devcard Kit without having to buy it in a package deal (with an ST)? I've tried Best Electronics, and he will not split them up...can't say that I blame him.

Help please!

Can you explain what a devcard kit is? Would this allow me to test 7800 games on real hardware?

[Sub(Function(:))]

Quote

Can you explain what a devcard kit is? Would this allow me to test 7800 games on real hardware?

check out the bottom of this page.

This was a card that plugged in to the 7800 cart port and the a cable went to the ST Printer port. You could then up load software into the card's on board ram and test it live on the system.

These are hard to get now, I guess Best Electronics have sold there stock as they are not listed on the web site any more. Plus you need an ST to run the software.

A better solution now is found on Eckhard Stolberg's site. this is DIY project and works with a PC. You will need a PC with a parallel interface an a bit of moding to your 7800 and a cartridge.

[primeform]

Thanks alot sub! very helpful +rep

[Mitch]

Also, see here.

Mitch

[kamakazi]

Mitch, on Wed Feb 24, 2010 11:57 PM, said:

Also, see here.

Mitch

Thank you for posting that link Mitch...I've been looking for those since the links I had are dead. Incidentally, does anyone know what capacitor types were used on this devcard and if others can be used in their place?

[Mitch]

kamakazi, on Thu Feb 25, 2010 2:01 AM, said:

Mitch, on Wed Feb 24, 2010 11:57 PM, said:

Also, see here.

Mitch

Thank you for posting that link Mitch...I've been looking for those since the links I had are dead. Incidentally, does anyone know what capacitor types were used on this devcard and if others can be used in their place?

The capacitor at C1 is an electrolytic, the rest are monolithic caps.

Mitch

[kamakazi]

Thanks Mitch! Here's another question...what was the memory type used on this card? I couldn't cross-reference it.

[Mitch]

kamakazi, on Thu Feb 25, 2010 7:23 PM, said:

Thanks Mitch! Here's another question...what was the memory type used on this card? I couldn't cross-reference it.

Mine are 58256 RAM chips made by Sony. I think the more common part number is 62256. Different manufacturers sometimes use different part numbers for the same chips.

Mitch

[kamakazi]

Mitch, on Thu Feb 25, 2010 8:52 PM, said:

kamakazi, on Thu Feb 25, 2010 7:23 PM, said:

Thanks Mitch! Here's another question...what was the memory type used on this card? I couldn't cross-reference it.

Mine are 58256 RAM chips made by Sony. I think the more common part number is 62256. Different manufacturers sometimes use different part numbers for the same chips.

Mitch

Instead of a part number, would you happen to know what type of memory it is? By this I mean the size and speed.

[Mitch]

kamakazi, on Fri Feb 26, 2010 1:19 AM, said:

Instead of a part number, would you happen to know what type of memory it is? By this I mean the size and speed.

It's 256Kbits or 32KBytes, 120ns.

Mitch

[kamakazi]

Mitch, on Fri Feb 26, 2010 1:35 AM, said:

kamakazi, on Fri Feb 26, 2010 1:19 AM, said:

Instead of a part number, would you happen to know what type of memory it is? By this I mean the size and speed.

It's 256Kbits or 32KBytes, 120ns.

Mitch

Thanks again Mitch. This was all I could find that comes close. Would you know of any other place that sells ICs other than Digi-key and/or Radio Shack?

http://search.digike...e=428-2037-5-ND

[Mitch]

kamakazi, on Fri Feb 26, 2010 2:03 AM, said:

Thanks again Mitch. This was all I could find that comes close. Would you know of any other place that sells ICs other than Digi-key and/or Radio Shack?

http://search.digike...e=428-2037-5-ND

That one from digikey is a little bit faster but it's the same chip. Are you trying to build repros of the devcard?

Mitch

[gdement]

Jameco has 62256's:
http://www.jameco.co..._type=jamecoall


As you may have noticed, digikey doesn't actually have them in stock and they call it an "obsolete item - call". They probably won't be able to get any, they'll just tell you to buy something else.

Edited by gdement, Sat Feb 27, 2010 5:17 AM.

[kamakazi]

Mitch, on Fri Feb 26, 2010 12:22 PM, said:

kamakazi, on Fri Feb 26, 2010 2:03 AM, said:

Thanks again Mitch. This was all I could find that comes close. Would you know of any other place that sells ICs other than Digi-key and/or Radio Shack?

http://search.digike...e=428-2037-5-ND

That one from digikey is a little bit faster but it's the same chip. Are you trying to build repros of the devcard?

Mitch

Well, that's the idea. I have a friend who can produce the BIOS chips for them, leaving me to do the rest.

[kamakazi]

gdement, on Sat Feb 27, 2010 5:15 AM, said:

Jameco has 62256's:
http://www.jameco.co..._type=jamecoall


As you may have noticed, digikey doesn't actually have them in stock and they call it an "obsolete item - call". They probably won't be able to get any, they'll just tell you to buy something else.

Thanks for that link! That helped me track down most of the items I couldn't find. That only leaves finding the PAL and Atari chips. I also need to find the capacitors that were used. I figure Best Electronics will have the PAL and CO chip, not sure where I'm going to find those capacitors.

[kamakazi]

Mitch, since you have one, would you be so kind as to post the measurements of the devcard here so I can look for an appropriately sized blank PCB board?

[Shawn Sr.]

kamakazi, on Sat Feb 27, 2010 8:26 PM, said:

Mitch, since you have one, would you be so kind as to post the measurements of the devcard here so I can look for an appropriately sized blank PCB board?

Odds are you could compact the design down to the size of a normal 7800 game pcb. You could use much larger sram chips and just change how the banks are controlled. That is unless your looking to make 1-1 repros.

[kamakazi]

Shawn Sr., on Sat Feb 27, 2010 8:49 PM, said:

kamakazi, on Sat Feb 27, 2010 8:26 PM, said:

Mitch, since you have one, would you be so kind as to post the measurements of the devcard here so I can look for an appropriately sized blank PCB board?

Odds are you could compact the design down to the size of a normal 7800 game pcb. You could use much larger sram chips and just change how the banks are controlled. That is unless your looking to make 1-1 repros.

I've thought of that as most of the chips are now in surface-mount design. But there are three chips that are not, the PAL, Atari CO and the Eprom holding the devcard ROM. I may try to do both a 1-1 as Atari did it and a cartridge size version. I don't think I would change the specs away from what Atari used too much as it may pose problems later on.

[Shawn Sr.]

kamakazi, on Sat Feb 27, 2010 9:07 PM, said:

Shawn Sr., on Sat Feb 27, 2010 8:49 PM, said:

kamakazi, on Sat Feb 27, 2010 8:26 PM, said:

Mitch, since you have one, would you be so kind as to post the measurements of the devcard here so I can look for an appropriately sized blank PCB board?

Odds are you could compact the design down to the size of a normal 7800 game pcb. You could use much larger sram chips and just change how the banks are controlled. That is unless your looking to make 1-1 repros.

I've thought of that as most of the chips are now in surface-mount design. But there are three chips that are not, the PAL, Atari CO and the Eprom holding the devcard ROM. I may try to do both a 1-1 as Atari did it and a cartridge size version. I don't think I would change the specs away from what Atari used too much as it may pose problems later on.

If you need a source for the SRAM chips let me know. I can point you in the right direction to get them for a decent price.

[kamakazi]

I would like to see the direction you have in mind. As it is, the PAL chip is about the only chip I am in need of the most.

[Shawn Sr.]

kamakazi, on Sat Feb 27, 2010 9:48 PM, said:

I would like to see the direction you have in mind. As it is, the PAL chip is about the only chip I am in need of the most.

I just checked and my source is sold out Sorry about that.