[sane-devel] Canon DR-7550 I/O Error

[Furio Settimi]

Hi,
I have some problem with Canon DR-7550 on Slackware 13.37 with Sane 
V:10.0.22
When I try this command or other options, the report is every time this.
Example:

SANE_DEBUG_CANON_DR=25 scanimage  > file.tiff

....
[canon_dr] ssm_buffer: start
[canon_dr] do_usb_cmd: start
[canon_dr] cmd: writing 24 bytes, timeout 30000
[canon_dr] cmd: wrote 24 bytes, retVal 0
[canon_dr] out: writing 32 bytes, timeout 30000
[canon_dr] out: wrote 0 bytes, retVal 9
[canon_dr] out: wrong size 32/0
[canon_dr] ssm_buffer: finish
[canon_dr] sane_start: ERROR: cannot ssm buffer
[canon_dr] sane_start: error 9
scanimage: sane_start: Error during device I/O
[canon_dr] sane_cancel: finish
[canon_dr] sane_close: start
.....

thank You