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Re: Pictures from the Netherlands
> About Thomas Davis's bi-directional quickcam code, I couldn't quite
> get what is actually being done when reading data from the cam:
Someone mention my name?
>
> word1 = inw(port);
>
> while ((word1 & 0x01) != 0x01) {
> word1 = inw(port);
> }
>
> word1 = ((word1 & 0xff00) >> 3) | (word1 & 0x00ff);
> word1 = word1 << 1;
> word1 = ((word1 & 0x00ff) >> 2) | (word1 & 0xff00);
>
> So for example in case we have the quickcam in port 0x378, we first
> read a byte from port 0x378 to the low-order byte of word1 and after
> that, a byte from port 0x379 to the high-order byte of word1, right?
>
> Then we handshake with the lowest-order bit from the data register
> input.. is it really so or did I get something wrong? Would be more
> logical if we still used bit 3 of the status register for handshaking
> as in the uni-directional mode, but...? And this code supposedly only
> works in either 4bpp or 6bpp mode?
Yup. You got it. We can't change it either.
As for modes, I can only say it works for 6bpp in bi-directional mode.
I have no idea what happens in the other mode..
6bpp, bidirectional is as fast as it will go.
There are major speed improvements that can be done to the qcam stuff from
Scott Laird. I don't have the time right now to clean it up....
I'm working on speeding up the other code (for those of you got the tar file)
But, it will be a few days..
(I've shown some of the code to my employees, and all they do is shake
their heads, mumble something about power trip, and go back to work..)
--
Thomas Davis | Internet: Thomas.Davis@mnscorp.com
Systems Consultant | Snail Mail: Suite 528
Midwest Network Solutions Corp. | 1941 South 42nd Street
(402) 346-7687 | Omaha, NE 68105-2939
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