C64 rev.2 7E17

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C64 rev.2 7E17

Francesco Messineo
Hi all,
I was reading the PLA dissected article and the author(s) state that
no rev.2  PLA was dumped. I think both my SX-64 have a REV.2 PLA (they
are 82S100).
Is it still true that we don't have a rev.2 dump? I think the final
logic results must be the same as rev.3 so maybe a logic map would
look identical to the rev.3 one?
Is it possible to recover the jedec once I finally get a PLS100/82S100
programmer?

Frank

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Re: C64 rev.2 7E17

fhw72
I've dumped both versions some years ago and compared the JEDEC files.
The were different but the differing terms were disable. In other words
the resulting functionality was 100% identical.

/Frank



--
Sent from: http://cbm-hackers.2304266.n4.nabble.com/

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Re: C64 rev.2 7E17

Francesco Messineo
On Fri, Apr 5, 2019 at 9:42 PM fhw72 <[hidden email]> wrote:
>
> I've dumped both versions some years ago and compared the JEDEC files.
> The were different but the differing terms were disable. In other words
> the resulting functionality was 100% identical.

Thanks Frank :) So I won't need to read a rev.2 unless I'm really sure
it's safe once I get a programmer.

Frank (yet another one)

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Re: C64 rev.2 7E17

peter
In reply to this post by fhw72
> I've dumped both versions some years ago and compared the JEDEC files.
> The were different but the differing terms were disable. In other words
> the resulting functionality was 100% identical.
>
> /Frank
>
>

Are there any clues to previously unknown modes or memory maps hidden in
the disabled terms?

-Pete


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Re: C64 rev.2 7E17

fhw72
I can't recall... but I can look on my backups in the next few days
and post both JEDECs. Maybe someone wants to take a look at it?



--
Sent from: http://cbm-hackers.2304266.n4.nabble.com/

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Re: C64 rev.2 7E17

Daniel V. Mackey
In reply to this post by fhw72
At 05:59 PM 4/5/2019, you wrote:

I programmed an EPROM (27C512-64k) PLA a few years back with a
Promenade C1 programmer. I had to program the upper 32k then do the lower 32k.

It works but some programs cause artifacts on the screen BUT it does work.


>I've dumped both versions some years ago and compared the JEDEC files.
>The were different but the differing terms were disable. In other words
>the resulting functionality was 100% identical.
>
>/Frank
>
>
>
>--
>Sent from: http://cbm-hackers.2304266.n4.nabble.com/

---
WWW: http://www.commodoredungeon.com

QUOTE : "A Clean bench is a sign of a weak mind."


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Re: C64 rev.2 7E17

Clockmeister


Hi Dan, all,

Yes I can verify that it does work, one of my C64's still has an EPROM
replacement PLA. I remember experimenting at the time and finding some
EPROMĀ  type/speed combinations worked better than others. The one I
ended up going with one that seemed to work 100% as far I could tell
without testing every program in existence.

On 6/04/2019 5:04 am, Daniel V. Mackey wrote:

> At 05:59 PM 4/5/2019, you wrote:
>
> I programmed an EPROM (27C512-64k) PLA a few years back with a
> Promenade C1 programmer. I had to program the upper 32k then do the
> lower 32k.
>
> It works but some programs cause artifacts on the screen BUT it does
> work.
>
>
>> I've dumped both versions some years ago and compared the JEDEC files.
>> The were different but the differing terms were disable. In other words
>> the resulting functionality was 100% identical.
>>
>> /Frank
>>
>>
>>
>> --
>> Sent from: http://cbm-hackers.2304266.n4.nabble.com/
>
> ---
> WWW: http://www.commodoredungeon.com
>
> QUOTE : "A Clean bench is a sign of a weak mind."
>
>
>


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Re: C64 rev.2 7E17

Gerrit Heitsch
In reply to this post by Daniel V. Mackey
On 4/5/19 11:04 PM, Daniel V. Mackey wrote:
> At 05:59 PM 4/5/2019, you wrote:
>
> I programmed an EPROM (27C512-64k) PLA a few years back with a Promenade
> C1 programmer. I had to program the upper 32k then do the lower 32k.
>
> It works but some programs cause artifacts on the screen BUT it does work.

Yes, that's caused by the difference in the way an EPROM works compared
to a real PLA.

  Gerrit



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Re: C64 rev.2 7E17

Segher Boessenkool
In reply to this post by fhw72
On Fri, Apr 05, 2019 at 03:56:58PM -0500, fhw72 wrote:
> I can't recall... but I can look on my backups in the next few days
> and post both JEDECs. Maybe someone wants to take a look at it?

Yes, I'd love to.


Segher

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Re: C64 rev.2 7E17

silverdr@wfmh.org.pl
In reply to this post by Clockmeister


> On 2019-04-06, at 06:25, Clockmeister <[hidden email]> wrote:
>
> Hi Dan, all,

Hi Clocky.

> Yes I can verify that it does work, one of my C64's still has an EPROM replacement PLA. I remember experimenting at the time and finding some EPROM  type/speed combinations worked better than others.

That's understandable as "it's all about timings".

> The one I ended up going with one that seemed to work 100% as far I could tell without testing every program in existence.

Could you tell which one was that?

--
SD! - https://e4aws.silverdr.com/


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Re: C64 rev.2 7E17

Clockmeister


On 7/04/2019 11:50 pm, [hidden email] wrote:

>
>> On 2019-04-06, at 06:25, Clockmeister <[hidden email]> wrote:
>>
>> Hi Dan, all,
> Hi Clocky.
>
>> Yes I can verify that it does work, one of my C64's still has an EPROM replacement PLA. I remember experimenting at the time and finding some EPROM  type/speed combinations worked better than others.
> That's understandable as "it's all about timings".
>
>> The one I ended up going with one that seemed to work 100% as far I could tell without testing every program in existence.
> Could you tell which one was that?

Not easily. I have quite a number of C64's and I didn't make a note of
which one it was - and it was years ago now. If I get the time I will
open them up, find the one and let the you know via the list.


>