[sane-devel] Genesys GL846/847 trying to add new scanner

[Radoslav Kolev]

On Sat, Nov 3, 2012 at 10:36 AM, Stef <stef.dev at free.fr> wrote:
> On 02/11/2012 21:13, Radoslav Kolev wrote:
>     the only public documentation from genesys logic is the register
> description you already found. Firmware functions have been reversed
> engineered. When there are many reads and writes, it could be hardware
> setting and polling and so GPIO related.

OK, so more probing and guessing is required.

>     The MPENB use is a new feature that I haven't implemented in the genesys
> backend, and will have to be added. Unless you create proper slope tables
> and make this model work like the others.

I'm not really clear with the terminology yet. I think the motor phase
and slope tables are separate things. Because there are also slope
tables being uploaded here (which my guess is are
acceleration/decelleration data). The MPENB is more about  full/half
step and which motor phase sequence activation.

If MPENB is disabled, where does the motor phase sequence come from?

>     Sometimes it is safe to drop some unidentified reads. For instance I
> have found writes that could be image watermark with the CCD sensor name.
> Sometimes you don't really find what they are for, but you have to implement
> them to get the scanner working.

I noticed that very frequently after register read/writes some GPIOs
are being toggled. Do you think it will be useful to try and trace out
which GPIO is connected to what. Can you give some hints like what
besides buttons might be connected to the GPIOs.

>     I have learned that a lot of experimenting and testing is needed to get
> these scanner work. For instance I was blocked by an undocumented register
> (or buggy write to a register) that was required to get correct scanned
> data.

Yes, I bet it is not easy. Kudos for the great work! I hope with some
help we'll be able to get this thing working.

Best regards,
Radoslav