Hi Jan, thank you very much indeed for those information. Your git repo is exactly what I have been looking for. I already compiled it but had some issues, which I need fix first. Sent you a private mail already, too.
I'm glad to see the amount of work you already put into the mustek_usb2 sources. Will try to get it running here, too. Chris Jan Hauffa wrote: > A year ago, I was in the same situation as you: I had just bought a > Medion MD90093 (USB product ID 0x3025, same as the MD90100), found out > it was using the SQ113 chip, and tried to make it work with the > mustek_usb2 backend. There are two issues with this approach: > > 1) The SQ113 is a rather primitive chip. As you can see from the > (otherwise mostly useless) data sheet [1], it is basically a USB > interface to a 8031 CPU with some ROM and RAM, which in turn > communicates with a number of external components: SDRAM for buffering > image data, a motor driver, and a CCD sensor. This is convenient for the > manufacturer, as they can just throw together whatever components they > can get cheaply, but highly inconvenient for us, as a driver for a > specific SQ113-based scanner is unlikely to work for another model with > a different set of external components. Even worse, the communication > protocol is mostly determined by the firmware, and so far I've seen > three different firmware variants "in the wild". > > 2) The mustek_usb2 backend is a mess, it contains lots of dead code and > copy & pasted code with subtle differences between the copies. Also, it > has been written specifically for the "Mustek BearPaw 2448 TA Pro", and > its design does not lend itself to adding support for different motor > drivers, CCDs, etc. > > I've done a lot of refactoring on the mustek_usb2 backend, but so far I > have been unable to test it for regressions with an actual BearPaw 2448 > TA Pro. Recently I have acquired one of these scanners, but it has a > mechanical defect which I have to fix before I can run any tests. > > Furthermore, I've logged some of the USB traffic between the Windows > driver and the MD90093, and attempted to modify the backend accordingly. > Motor movement appears to work, but the CCD parameters are not yet set > correctly. > > I've published the code on github [2], it might be useful for you if you > decide to use the mustek_usb2 backend as a base. I'm enthusiastic about > making this scanner work with SANE, but unfortunately I really lack free > time to work on this project. However, feel free to contact me off-list > if you have any questions. > > Best regards, > Jan > > > [1] http://yc-dz.com/productimages/11477678.pdf > [2] https://github.com/jhauffa/sane-sq113 > >
