[sane-devel] How far to go for the CanoScan LiDE 500F

[Pierre Willenbrock]

Michael Roitzsch schrieb:
> Since the CanoScan LiDE 500F is still unsupported and I consider to  buy
> such a thing, I would like to now, how much work is still missing  on
> this. I have some usable programming skills, but I have no  experience
> in reverse engineering USB protocols, so it would be nice,  if I had
> some idea about the task ahead. Thanks.

Basic reflective scanning may work with only adding the usb-id and a new
device definition to the backend.

But getting infrared scan and transparency adapter to work will require
capturing and analysis of usb logs of a scan with the windows driver.

I think these are the steps needed for full support:
- acquire logs from windows scans
- extract registers+motor tables
- find differences
- add support for reflective scanning for this model
- implement basic transparent scanning
- add calibration for transparent scanning
- add support for infrared scanning mode(probably a gray scanning mode
with a gpio pin set)

We do have some scripts for analysing usb logs. I can help finding the
differences between the register sets and motor tables of LiDE 500F and
mine LiDE35.

Getting reflective scanning to work should be easy, but there is
currently no support for transparent scanning and infrared scanning in
the gl841 part.

Regards,
  Pierre