Denial

As some of you may have noticed, over the last 2 years, I have invested time and energy developing replacements for a few custom chips used in Commodore 8 bit computers.

These include:
- PLAnkton which replaces the C64/SX-64 programmable logic array 906114-01 or 251064-01
- TOLB which replaces the 7701/8701 clock generator used on later C64 boards, the C64c and the C128
- GandALF which replaces the 1541 custom controller and array 325572-01

I am presently considering the possibility of making PLA replacements for the C64c board 250469, specifically part no. 251715-01. Board 250469 can use 2 different types of PLA which incorporates most of the glue logic ICs used in the original C64 and they are part no. 251715-01 and 252535-01. Making PLA 252535-01 may prove too difficult because it incorporates the 512x4 bits color RAM and this type of chip is no longer in production.

So far, I did not make this substitute strictly because there doesn't seem to be much interest, not because there are any technical hurdles I can't overcome. This variant of the PLA is based on more modern technology than the one employed on 28 pin PLAs and it doesn't produce any discernable heat so it fails far less frequently.

I would like the people of Denial to indicate if there is, in fact, sufficient interest to make a substitute for PLA 251715-01 used on board 250469 and how much people would expect to pay for this replacement.

Thank you all for your feedback.

- Francois

I would be interested. Maximum price - no more than $25.

Writing from Ventura, California,
Robert Bernardo
Fresno Commodore User Group
http://www.dickestel.com/fcug.htm
Southern California Commodore & Amiga Network
http://www.portcommodore.com/sccan

@RobertBe
25$US or 21.50 Euros seems like an adequate price point.

eslapion wrote:25$US or 21.50 Euros seems like an adequate price point.

Oh, I wasn't considering other monetary units. That would be $31.93 Canadian.

Writing from Castaic, California,
Robert Bernardo
Fresno Commodore User Group
http://www.dickestel.com/fcug.htm
Southern California Commodore & Amiga Network
http://www.portcommodore.com/sccan

RobertBe wrote:

eslapion wrote:25$US or 21.50 Euros seems like an adequate price point.

Oh, I wasn't considering other monetary units. That would be $31.93 Canadian.

The value of the Canadian dollar varies constantly and very few people use that currency to pay me. By default I charge in US$ and all the parts I buy are paid in US$ too.

Well... Something wicked this way comes!

After a bit of investigation, it seems the price of this product will have to be higher. The price of the pin headers required is 21 times higher than those used on PLAnkton and TOLB. This is because of the non-standard 1.78mm pitch. Every other Commodore IC has a 2.54mm (0.1") pitch.

The upside is the much thicker gold plating on the pins. Normal plating is 3uin or same as ENIG, the special pins on MegaPLAnkton will be 10uin or same as hard gold plating.

This product is expected to be priced at 30 Euros or 34.50$US.

Hello as there are now new 250469 Board aviable there might be more interrest in the MegaPLA

https://www.tindie.com/products/bobsbit ... lica-pcbs/

Just a thought.

crisp wrote: ↑Sat May 02, 2020 10:39 am Hello as there are now new 250469 Board aviable there might be more interrest in the MegaPLA

https://www.tindie.com/products/bobsbit ... lica-pcbs/

Just a thought.

Unfortunately, I recently had a major setback in the development of MegaPLAnkton. The fab I use to make most of my products only have certain types of logic ICs and in limiting myself to these ICs, I seem to have made a mistake and my 1st prototype is a dead horse.

Concerning the Sixtyclone, I would say my favorite board is the clone of the 250466 as it is compatible with PLAnkton, Saruman-64 and TOLB.

Here is another Project which would use a new megaPLA

https://www.forum64.de/index.php?thread ... ing-board/

crisp wrote: ↑Thu May 07, 2020 3:57 pm Here is another Project which would use a new megaPLA

https://www.forum64.de/index.php?thread ... ing-board/

Yeah, I read a bit about it. I can only use Goggle Translate with German.