PLAdvanced(+) Universal (9) PLA replacement

Brotboxfan

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As it's getting more difficult to find the right spare parts we (Freak, androSID and I)
thought we might build something for our stock of spare parts:

PLAdvanced(+)

This new PLA combines up to 9 different 28 pin PLA from C= machines in one:


  • C64 / SX64 (no 250496 Board)
  • 1551
  • CBM 6x0
  • CBM 7x0
  • C16 / plus4
  • CBM 8296 UE5
  • CBM 8296 UE6
  • P500 U78
  • P500 U88

Configuration will be done via solder joints or via DIP-switches.

So you don't need to keep several PLA but just one!

PLAdvanced+ with DIP- switches
PLAdvanced+.jpg

This is the small version PLAdvanced including 4 PLAs to show the solder joints
PLAdvanced.jpg
 
well done!
what is about SID? Will there be a new replacement with mouse/paddle support soon?
 
well done!
what is about SID? Will there be a new replacement with mouse/paddle support soon?
No.
SID replacement with mouse/paddle support is available and works fine.
SwinSID ultimate and FPGASID.
 
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I'm glad to see somebody else used my 74LS279 PLA tester circuit.

However, I have to indicate PLAdvanced does not appear to have the proper CASRAM latency required for C64 boards 326298, KU-14194 and early versions of the 250407.

AFAIK, only these c64 boards have specific requirements for latency on one of the PLA output for proper DRAM access.

AFAIK, Other Commodore 8 bit products which use the PLA have no such requirements so PLAdvanced should work with everything else.
 
I'm glad to see somebody else used my 74LS279 PLA tester circuit.

However, I have to indicate PLAdvanced does not appear to have the proper CASRAM latency required for C64 boards 326298, KU-14194 and early versions of the 250407.

What did you do to come to this conclusion? Did you actually measure the CASRAM# latency or is this just guessing?
Or maybe you got your hands on one of the early prototypes because I cannot recall that you bought
the final PLAdvanced officially? :D

Apart from that we've measured the latency on several revisions of the C64 board (up to C64R) and the latency
was always in the same ballpark as all PLAs supplied by C= we've had at hand (early ceramic 93459, 82S100, PLS100, 251064-01
and of course "standard" 906114-01 with either 7700 or 8700 silicon die in it.).

That means: PLAdvanced is neither worse nor better than your Plankton... it's just more versatile and worthwhile than Plankton. :cool:

Developing a PLA replacement is NOT rocket science! :thumbsup2: Everyone can do that.
In other words: Should we ever face an incompatibility we'll address that of course...

BTW: We've even reduced the voltage at the outputs from PLAdvanced to ~4,2Volt to simulate the original PLAs from C= (~3,8V-4,3V).
I did not see that on other PLAs! Most other (pure) CPLD-based are limited to ~3,3Volt at their outputs (except when using some excess voltage
or legacy products).
 
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... the latency
was always in the same ballpark as all PLAs supplied by C= we've had at hand (early ceramic 93459, 82S100, PLS100, 251064-01
and of course "standard" 906114-01 with either 7700 or 8700 silicon die in it.).
The CASRAM latency on genuine Commodore PLAs varies from 28ns to 40ns. It's a pretty wide range. Same ballpark?

Developing a PLA replacement is NOT rocket science! :thumbsup2: Everyone can do that.
In other words: Should we ever face an incompatibility we'll address that of course...
I saw this with Mytec's PLAtinum and the SuperPLA... :roll:

If everyone can do it then why is it nobody does it?

BTW: We've even reduced the voltage at the outputs from PLAdvanced to ~4,2Volt to simulate the original PLAs from C= (~3,8V-4,3V).
I did not see that on other PLAs! Most other (pure) CPLD-based are limited to ~3,3Volt at their outputs (except when using some excess voltage
or legacy products).
Reduced?

PLAnkton signals at an increased 0-3.7V since it was introduced in August 2015. J-PLA signals at 0-3.6V since it was introduced too. If 'Most other (pure) CPLD-based are limited to ~3,3Volt at their outputs" why is it I don't know of any that have such limitation?

BTW, I did not mention PLAnkton in my previous post because there are actually now many other products which use CPLDs and have the proper CASRAM latency and signal at the correct voltage. If you 'did not see that on other PLAs' then I strongly suggest you watch this video:
https://www.youtube.com/watch?v=ofg33zk9uCA

I guess imitation is the sincerest form of flattery...
 
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Developing a PLA replacement is NOT rocket science! :thumbsup2: Everyone can do that.
In other words: Should we ever face an incompatibility we'll address that of course...
I saw this with Mytec's PLAtinum and the SuperPLA... :roll:

If everyone can do it then why is it nobody does it?


I guess imitation is the sincerest form of flattery...

Imitation of what: PLAnkton? SuperPLA? ...

I can't remember that you ordered one.

How can you compare PLAdvanced with other PLA :whistle:

We made no Mytec's PLAtinum and no SuperPLA.

It's PLAdvanced we made.

We Know You are able to make a PLA for different Commodore computers.

Why I can't by your version of multiPLA today?

When you bring out your version of multiPLA next time, is this imitation too? :shhh:
 
How can you compare PLAdvanced with other PLA :whistle:
You're taking what I said out of context.

In response to 'Developing a PLA replacement is NOT rocket science!
thumbup.gif
Everyone can do that.
', I was indicating that Mytec's PLAtinum and IC's SuperPLA have serious technical flaws. I was not comparing your product.

We made no Mytec's PLAtinum and no SuperPLA.
Same as above.

We Know You are able to make a PLA for different Commodore computers.
You do? I didn't know that...

I elected to make one only for the Commodore 64 because I noticed many other products didn't account for more than just the logic equations.

You have chosen to create a PLA substitute which seems to work on other Commodore 8 bit products and I think it's great. I am simply too busy with other stuff to invest time and energy in this avenue.

Why I can't by your version of multiPLA today?
Same as above.

When you bring out your version of multiPLA next time, is this imitation too? :shhh:
I make PLAnkton as a favor to the Commodore community, not because I have a strong interest.

I did receive e-mails pressuring me into making other PLA subs but I wasn't so sure I would do it. If you make a good product, why would I compete?

There are many other items much higher on my 'to do' list.

Added edit:
The point of my original post about the CASRAM latency was actually to help you make your product better. I am confronted with a 'mine is better/bigger than yours' kind of answer... rather childish.

I am no longer interested in making PLAs. Getting the XC9536XL CPLD is more and more of a struggle with Digikey either not carrying them or pumping up the prices to new heights.
 
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I'm glad to see somebody else used my 74LS279 PLA tester circuit.

However, I have to indicate PLAdvanced does not appear to have the proper CASRAM latency required for C64 boards 326298, KU-14194 and early versions of the 250407.

AFAIK, only these c64 boards have specific requirements for latency on one of the PLA output for proper DRAM access.

AFAIK, Other Commodore 8 bit products which use the PLA have no such requirements so PLAdvanced should work with everything else.

PLAdvanced does not appear to have the proper CASRAM latency required for C64 boards 326298 ?

To say it without to hold one in your hand is help?

That's why I'm so childish.

We are interested in help for all mistakes we made.

C64_NTSC_ASSY236298.jpg C64_NTSC_ASSY236298_b.jpg
PLA_Collection.jpg

Did you contact me via mail I understand your helping hand. So I don't feel denounced.

Yes I've seen your video before:

https://www.forum64.de/index.php?th...-ein-assy-250407b/&postID=1258756#post1258756

It's not our aim to say PLAdvanced is better then PLAnkton.
 
PLAdvanced does not appear to have the proper CASRAM latency required for C64 boards 326298 ?

To say it without to hold one in your hand is help?

That's why I'm so childish.

Saying something like
'Developing a PLA replacement is NOT rocket science! :thumbsup2: Everyone can do that.
In other words: Should we ever face an incompatibility we'll address that of course...'
is both childish and irresponsible but that's not from you. It indicates the development is a PLA replacement is not taken seriously at all.

If you fix an incompatibility problem once you have hundreds of units sold then you have created a mess.

This being said...
If there is no CASRAM latency problem then it's a good thing. May I suggest you check it with a logic analyzer. Not just test a specific unit in one specific C64 with assy 326298.

Did you contact me via mail I understand your helping hand. So I don't feel denounced.
I did not contact you by e-mail.

It's not our aim to say PLAdvanced is better then PLAnkton.
And I didn't claim PLAnkton is better than PLAdvanced. I noted a specific potential issue.
 
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If there is no CASRAM latency problem then it's a good thing. May I suggest you check it with a logic analyzer.
Not just test a specific unit in one specific C64 with assy 326298.

Been there... done that!

Thanks for your feedback and goodbye! :D

- - - Updated - - -

... PLAnkton signals at an increased 0-3.7V since it was introduced in August 2015....

This is interesting because the recommended operating voltage for VCCio states a maximum voltage of 3.6Volt.


Anyway: Thanks for your feedback... we really appreciate that.
 
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... PLAnkton signals at an increased 0-3.7V since it was introduced in August 2015....

This is interesting because the recommended operating voltage for VCCio states a maximum voltage of 3.6Volt.

NOOO!!!!!!
Oh my God!

May I let gain you a lot of endless pages of disquisition?
The Plankton power supply bug (as project choose) was discussed here:
http://sleepingelephant.com/ipw-web/bulletin/bb/viewtopic.php?f=11&t=8764&hilit=mces&start=60#p97607

The effect of this on a real Plankton was measured here:
http://sleepingelephant.com/ipw-web/bulletin/bb/viewtopic.php?f=12&t=8913&hilit=mces&start=15#p99424

Everybody can read and deduce own idea about it.

Good luck...

 
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Thanks to Eslapion for the suggestion....

"The effect of this on a real Plankton was measured here:"
I swapped a PLA of mine for a planktn: now I can measure something...

On my C64 motherboard I desoldered a side of L5 to feed the 5V line from another (variable) PSU, the results:
(4.75-5.25 is the narrowest Recommended Operation Conditions (ROC) of C64 chips).

(V28-14 is the voltage between Pin28 and Pin14 of PLA before diode resistor, Vcpld is measured after diode-resistor).

V28-14 / Vcpld
4.75 / 3.52
4.85 / 3.595
4.95 / 3.67
5.00 / 3.71
5.05 / 3.745
5.15 / 3.819
5.25 / 3.895

From the real world we can note....

First note: if the target is to supply the CPLD with not less of 3.6V (for guarantee a prefixed Voh) plankton don't meet this with a permitted V28-14 equal or below 4.85V (4.75...4.85V).

Second note: the Vcpld increasing is linear with V28-14 increasing (75%), so the suggestive theory about aliens that use capacitors energy to transform a CPLD in a zener diode is demonstrated to be a FAKE: it's a fact.

Through this linear law (measured into the real world), it's possible to estimate:
A) 4Vcpld will reached with V28-14 of 5.39V
B) with the AMR of the chips inside C64 (7V) the Vcpld will be around 6.56V (2.56V beyound the "mortal point" of 4V): a very good work!

Plankton is suffering by a wrong project choose: it need a precise Vcpld of 3.6V but it was obtained with a diode and dropping resistor that not guarantee the right value of 3.6V.
 
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Plankton is suffering by a wrong project choose: it need a precise Vcpld of 3.6V but it was obtained with a diode and dropping resistor that not guarantee the right value of 3.6V.
MCes is suffering from a wrong vocabulary choose...

Anyways, PLAnkton runs at 3.7V and it is not a bug. It's intentional since Skoe indicated genuine Commodore PLAs signal at 0-3.7V. http://www.zimmers.net/anonftp/pub/c..._Dissected.pdf

I checked my own prototypes at 4.3V for extended periods of time before making this choice. No problem at all.

As you said yourself...
[FONT=&quot]
BLA BLA = value ZERO,
[/FONT]
 
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Plankton is suffering by a wrong project choose: it need a precise Vcpld of 3.6V but it was obtained with a diode and dropping resistor that not guarantee the right value of 3.6V.
MCes is suffering from a wrong vocabulary choose...

.......... TL;DR......

As you said yourself...
BLA BLA = value ZERO,

If anyone here is suffering from wrong vocabulary choose: I think it's you! See below:

.... However, I have to indicate PLAdvanced does not appear to have the proper CASRAM latency required for C64 boards 326298, KU-14194 and early versions of the 250407....

Stating that "PLAdvanced does not appear to have the proper CASRAM latency required" without ever having measured this.....

.... Added edit: The point of my original post about the CASRAM latency was actually to help you make your product better....

.... is not helping to make a product better! It's just bad-mouting a product (for obvious reasons).

eslapion said:
MC Scratchy ? :D

I still haven't made up my mind if this is an insult or just childish? :roll:

eslapion said:
Well, if you 2 guys are right, I should just stop offering PLAnkton right away. Now should I ?

I don't care what you do... really. And I certainly do not give any advise on this. Just do what ever you want to do! :)

PS: Maybe just stop fighting against MCes and/or me in this thread! It's the photo booth here....
 
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