Re: Connectix: Mac vs PC

Larry Chace (RLC1@cornell.edu)
Wed, 28 Jun 1995 23:07:27 -0400


Roger Boston suggested re-wiring the Mac version of the Connectix QuickCam
so that it could be plugged into a PC's serial port.

Go ahead and try it. Oh, you might want to consider a couple of things:
1. Mac serial ports use RS-422, with differential signals. PC serial ports
use RS-232, with non differential signals of a higher voltage.
2. Mac serial ports run can run at a high speed, depending upon model, but
always at least at LocalTalk speeds (about 230Kbaud). PC serial ports are
typically limited to lower speeds, perhaps around 30Kbaud. At, say, 4 bits
per pixel, think how long it would take to read in an image that was, say,
160 by 120 pixels. Hm.....
3. The QuickCam is *not* a standard video camera. It needs software on the
"inside" of the serial port to process the data. When you bought your Mac
QuickCam, Connextix provided a video driver routine and an audio driver
routine. These are for the Mac; they will not run on the PC.

When Connectix has their PC QuickCam working and when they have FCC
approval to sell it, then they will. They will also provide the necessary
PC driver routines. I'm quite sure that they *want* to sell it as soon as
possible.

But, if you can't wait, go ahead with your wire cutters and soldering iron.
You'll have fun, at least for a little while. Then you can frame the
remains of your (Mac) QuickCam and hang it on the wall as a trophy. (And
don't try to ask for your money back!) ;-)

Larry Chace (RLC1@cornell.edu)