Re: Computist Issue 30

[Sheldon Simms <sheldonsimms@yahoo.com>]

On Thu, 26 Feb 2004 21:38:55 -0500, Bill Garber wrote:

> 
> "Jeff Blakeney" <CUTjblakeney@sympatico.ca> wrote in message
> 8f1t30pot2ljpqp020phqmioiltsai4b7t@4ax.com">news:8f1t30pot2ljpqp020phqmioiltsai4b7t@4ax.com...
> : On Wed, 25 Feb 2004 19:58:52 -0500, "Bill Garber"
> : <willy46pa@comcast.net> wrote:
> :
> : >If they can go to 600 wide, the length should not
> : >matter too much. They should scroll ok then. Also,
> : >if you get Spectrum Web Browser, you could make
> : >them HTML files at 600 wide and view them ok, I
> : >would think.
> :
> : Neither of the web browsers available for the IIgs (Spectrum
> Internet
> : Suite or Arachnid) nor the other programs that allow you to
> view or
> : convert HTML files (ie. Spectrum editor, WebWorksGS, Babelfish
> HTML
> : translator) support images of any kind.  Making JPEG or PNG
> images
> : into HTML would require OCR'ing them to turn them into text and
> then
> : adding the HTML elements that would make it worthwhile viewing
> it as a
> : web page.
> 
> Oh yeah, I fergot. Sorry.
> 
> : >Not to mention that there are not many Second Sight video
> : >cards to be had. How many of us actually has one. Not Me!
> : Yeah, I know.  I don't have one either but I thought I'd
> mention it
> : for completeness.
> 
> If I could have gotten that developement package, we might
> have had something similar in a year, or maybe even better.
> But the price just got way too high for me. It makes my
> bones ache when I see things get to $500-$600+.

I have second sight schematics that I can scan in, but I doubt
they will be very helpful. The second sight isn't anything
special, hardware-wise. It's all about the firmware.

The second sight card consists of a Zilog Z180, an Oak VGA chip
(don't remember exactly which one, offhand), some memory and some
logic that lets the Z180 monitor the Apple II bus: In other words,
it is a small Z180 based microcomputer that simply runs an
Apple II video emulation program, no different than the video
emulation in a PC-based Apple II emulator.

The biggest problems with the Second Sight are:

  1. It is a power hog. It overloads the power supply and can
     cause general system instability if the Apple II power
     supply isn't upgraded.

  2. It is computationally underpowered. The Z180 can barely
     keep up with the job it has to do. This was recognized
     right from the beginning, but a Z180 was convenient for
     the designers because they were familiar with the chip,
     having used it for the RamFast. (or so I understand; I
     don't have a RamFast myself)

  3. The board was never really completed. I had to send my
     second sight card back to Sequential for hardware and
     firmware upgrades one time, and the firmware, especially,
     was still incomplete. It didn't even emulate all Apple II
     and IIe modes properly.

All of that is why I suggested taking the same concept, but
reimplementing it from scratch, using a modern low-power
CPU. Only, the CPUs are so fast these days, that you could go
ahead and toss in 65816 emulation as well and end up with an
card that acts like an accelerator as well.