[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: Apple //e hardware question
- Subject: Re: Apple //e hardware question
- From: mdj <mdj.mdj@gmail.com>
- Date: Wed, 22 May 2013 19:06:42 -0700 (PDT)
- Complaints-to: groups-abuse@google.com
- In-reply-to: <knjsps$8p3$1@dont-email.me>
- Injection-date: Thu, 23 May 2013 02:06:43 +0000
- Injection-info: glegroupsg2000goo.googlegroups.com; posting-host=113.197.125.40; posting-account=gKwMEAoAAACgdZoRArZlfcCSOA8KWMxg
- Newsgroups: comp.sys.apple2
- References: <knjjnt$4qa$1@dont-email.me> <feac9c85-3563-41fa-bc75-a88c3183578a@googlegroups.com> <knjsps$8p3$1@dont-email.me>
- User-agent: G2/1.0
On Thursday, 23 May 2013 11:59:24 UTC+10, Charlie wrote:
> The reason is, I'm going to add some Apple IIgs functions to my //e, and
>
> I want them to be compatible with a IIgs. So I want to use the same
>
> locations as the IIgs does. Specifically, I'm going to add Super HiRes
>
> graphics and I want the status of the softswitch/registers to be
>
> readable from //e programs.
Very cool! :-)
The Apple II Video Overlay Card does exactly this. ISTR it's documented in one of the Apple II technical notes. $2000-$9FFF of auxiliary memory holds the super hires display data, just as it does in bank $E1 on a IIgs.
The penny should have dropped when you mentioned $C029, but I guess it's been a while ;-)