[sane-devel] Canoscan lide100 progress

[Matt Hirsch]

I thought I'd update the list on my progress on the lide 100, in case 
anyone has any suggestions or comments that might be helpful.

The gl847 (chip in the lide 100) has a somewhat different protocol than 
the 841, specifically it uses single urb register reads (two urbs are 
usually required in the 841 protocol) and it handles bulk reads/writes a 
little differently. I've modified Pierre's script to parse the UsbSnoop 
output for the lide 100.

Modified script: http://web.media.mit.edu/~mhirsch/lide100/usbsnoop-gl847.pl
Original: http://pirsoft-dsl-dropzone.de/
Raw UsbSnoop output for a small scan: 
http://web.media.mit.edu/~mhirsch/lide100/UsbSnoop-3-scan.log.bz2
parsed output: 
http://web.media.mit.edu/~mhirsch/lide100/gl847-3-scan.out.bz2

There is no datasheet available for the gl847, but based on the usbsnoop 
log of the communication with the scanner it appears closest to the 
gl846, which is documented here: http://www.datasheetdir.com/GL846+USB

A driver for this chip seems like it would entail adding a 
backend/genesys_gl847.c and minor modifications to backend/genesys.c 
backend/genesys_low.h backend/genesys_devices.c (new CCD, GPO, and 
probably AFE and motor). Does this sound reasonable? I'm not familiar 
with SANE development at all.

Thanks very much to Allan for pointers in the right direction.

Matt