710/720 hires board found!

classic Classic list List threaded Threaded
3 messages Options
Reply | Threaded
Open this post in threaded view
|

710/720 hires board found!

vossi
Hi, I just found this Hires-Graphics-Extension in a B720. It plugs between
the Char ROM and the Screen Memory. It also plugs in the 74245 buffer U30 -
and the 245 is on the hires-board. It has 32kB dedicated ram. That's enough
for one page with 640x350 resolution monochrom. It had some wires to the
userport...
Has anybody Infos about this extension?

PS: The 720 is actually dead - so I'm not able to test it...

Here is a pic:
http://lc64.blogspot.de/2018/02/cbm-710720-hires-board-found.html



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

       Message was sent through the cbm-hackers mailing list
greets
Christian
Reply | Threaded
Open this post in threaded view
|

Re: 710/720 hires board found!

Steve Gray
Wow, nice! I’d love to see that reverse engineered!

Steve


> On Feb 18, 2018, at 11:28 AM, vossi <[hidden email]> wrote:
>
> Hi, I just found this Hires-Graphics-Extension in a B720. It plugs between
> the Char ROM and the Screen Memory. It also plugs in the 74245 buffer U30 -
> and the 245 is on the hires-board. It has 32kB dedicated ram. That's enough
> for one page with 640x350 resolution monochrom. It had some wires to the
> userport...
> Has anybody Infos about this extension?
>
> PS: The 720 is actually dead - so I'm not able to test it...
>
> Here is a pic:
> http://lc64.blogspot.de/2018/02/cbm-710720-hires-board-found.html
>
>
>
> --
> Sent from: http://cbm-hackers.2304266.n4.nabble.com/
>
>       Message was sent through the cbm-hackers mailing list


       Message was sent through the cbm-hackers mailing list
Reply | Threaded
Open this post in threaded view
|

Re: 710/720 hires board found!

Steve Gray
Hi all,

FYI, Christian provided me with lots of pictures of the board, and I have started reverse-engineering it. It's a nice little board that I hope to clone and/or improve.
You can find pictures, info, and work-in-progress schematics on GitHub here:


Steve



From: Steve Gray <[hidden email]>
To: [hidden email]
Sent: Saturday, February 24, 2018 6:16 PM
Subject: Re: 710/720 hires board found!

Wow, nice! I’d love to see that reverse engineered!

Steve


> On Feb 18, 2018, at 11:28 AM, vossi <[hidden email]> wrote:
>
> Hi, I just found this Hires-Graphics-Extension in a B720. It plugs between
> the Char ROM and the Screen Memory. It also plugs in the 74245 buffer U30 -
> and the 245 is on the hires-board. It has 32kB dedicated ram. That's enough
> for one page with 640x350 resolution monochrom. It had some wires to the
> userport...
> Has anybody Infos about this extension?
>
> PS: The 720 is actually dead - so I'm not able to test it...
>
> Here is a pic:
> http://lc64.blogspot.de/2018/02/cbm-710720-hires-board-found.html
>
>
>
> --
> Sent from: http://cbm-hackers.2304266.n4.nabble.com/
>
>      Message was sent through the cbm-hackers mailing list