> Message: 2 > Date: Mon, 28 Jan 2002 22:06:34 +0100 > From: Siegfried =?iso-8859-1?Q?L=F6ffler?= <[email protected]> > Reply-To: [email protected] > Organization: Private > To: [email protected] > CC: Theodore Kilgore <[email protected]> > Subject: Re: [sane-devel] Canon N670U > > This is a multi-part message in MIME format. > --------------4593554BF35A015A23D6C36A > Content-Type: text/plain; charset=us-ascii > Content-Transfer-Encoding: 7bit > > Hi, > > as the LM9833 chip used in the N670U should be backward compatible > to the LM9832/1 in the plustek backend, in theory it should not be > a big deal to make the N670U work. The only real difference is in the calibration routines - you would need to change on of the constants to account for the fact that the lm9833 returns 16 bits as opposed to 12.
However, there are a lot of parameters that you need to know to make the thing work properly - stepper motor distances, timing things etc - you can normally get these by USB snooping - at least that's what I did for the epson 1250 driver. > > However, in practice I did not manage it yet. > > What I did so far: > > I tried to find out the parametrs for the N670U by > > a) reading the NS LM9833 datasheet, available on the National Semiconductor > Website > as well as some useful information on http://connect.to/merlin/ > (information on the former versions of the LM9833 as well as source > code) > > and the URL mentioned by Gerhard Jaeger > http://scanjet2200c.sourceforge.net/ns-twain/ > > b) looking intensively at a trace made under Windows, using "USB Snoopy". > > In particular, I tried to make an entry in the plustek-devs.c based on the > parameters seen in the USB Snoopy Log File. But: Despite some small > progress (in the beginning, I always ended up stalled with an error when > trying to read register 7) I do not suceed to switch on lamp or motor of > the scanner yet. Sometimes the lamp isn't actually connected to the lamp outputs on the chip. Sometimes it's connected to one of the misc i/o pins. Helpful:) > > I also tried to run the driver on scanjet2200c.sourceforge under Windows, > but strange enough, I did not succeed to make that one work neither. (I get > an error that register 0x07 can not be read). So now I somehow wonder > whether there could be something particular inside the N670U. However, I do > not dare to open the device. Maybe somebody had opened it and could help by > describing what else (besides the LM9833) is on the mainboard? That sounds odd - I wonder if there's a problem with the USB setup somewhere? > > As I am currently quite busy with other stuff, I am afraid it might take > some time until I will be able to continue the tidious research studying > the USB Snoopy logfiles... Could you send me a copy of the logfiles - I'm trying to get a base together that will run any lm983[1/2/3] based scanner, with the hardware specified in a configuration for each scanner supported. Early days yet, though. > -- Phil Underwood. Curing disease, illness, and little flaky bits throughout the North-West --
