[Gumstix-users] USB camera on cfstix hack

[Pascal A. B. <pas...@wa...>]

The proper way to add a camera to the gumstix is with a CMOS sensor
controlled with I2C, clocked by a dedicated crystal, feeding data at
constant rate into a FIFO.  There's a nice paper explaining this, btw:
http://cswww.essex.ac.uk/mv/omnipapers/gwfran06with-header.pdf

Now if you don't have access to SMD manufacturing and don't mind erring
a little on the dark side of timing tolerances, there is another way:
- Disassemble a USB webcam
- Connect the data bus of its sensor to a cfstix
- Clock the sensor with nPIOR (the compactflash read strobe)
- Get raw sensor data by DMA'ing from compactflash address space.

Somehow, it works.  Details here:
http://perso.orange.fr/pascal.brisset/cfcam/

And my point is: if we had an ETA for a PXA270 product with hardware
video capture interface, I wouldn't be doing such horrible things :-)

-- P.