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What should the driver output?
Thomas Davis writes:
> 1. The driver should be a module.
Why does it have to run in kernel space? It doesn't need to field
interrupts, so it can just run as a setuid user-space program. It
needs to run as root because it needs access to the parallel port I/O
registers.
And not only that, but there's not much reason for the camera to be
sharable, so the code might as well be linked into a single program.
> 3. _What_ should the driver output?
>
> I've been puttering around with a driver based on someone's else driver
> (that is a module, but it's really, really skeleton), and it has a
> option based on how it was opened to put either bytes as is, or PGM
> format (portable gray map).
PGM. Raw mode PGM files are very easy to create.
> Oh, here's another one.
>
> 5. How many cameras per machine do we support? 1? There can be 3 LPT ports,
> so do we support upto 3 per machine?
Make the parallel port's I/O address be a command-line parameter.
-russ <nelson@crynwr.com> http://www.crynwr.com/~nelson
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