Acer (now Benq) 310P, 320P, 340P, 610P, 610PT, 620P, 620PT and 640P
Agfa SnapScan 310P, SnapScan EZ, SnapScan 1200P, SnapScan 1212P
"2103A" or "7107P" depending on scanner. 1212P has a 2103A.
The Agfa scanners seem to be be rebranded Acer scanners.
Daniel Glöckner explained several details of these scanners and sent a test program and a preliminary patch for the snapscan backend.
Looks like a SCSI-over-parport chip. At least under Windows 98 a "virtual" SCSI controller is installed (EPPSCSI).
Someone else also tried to get the 640P scanner supported, see this thread on sane-devel for details.
Regarding the Agfa SnapScan 1212P someone claims that it works with the plustek_pp backend.
If anything is wrong or missing on this page please file a bug report or use the the form for adding an unsupported device.
If you own an unsupported scanner, please send as much information as possible. Especially the output of sane-find-scanner -v -v and/or cat /proc/scsi/scsi (for SCSI scanners) or cat /proc/bus/usb/devices (for USB scanners) can help. If you dare to open the scanner, have a look at the text that's printed on the chips. That may help to identify the chipset. If you know that the scanner is similar to another one (e.g. supported by the same Windows driver), please also mention this fact.
Are you a manufacturer or vendor of scanners and one of your scanners is not supported by SANE yet? In this case please have a look at our information for manufacturers.