?

Log in

No account? Create an account

Previous Entry | Next Entry

Limited Success

I sat down tonight and hacked around with the code that Apple provided and have come to understand it reasonably well. I managed to get the driver code to find and connect to the scanner and open it's communication pipes.

So you'd think it's time to party, right? Nope, sorry. Now is when the work begins.

I've started reading the docs on the LM9833 chip that drives the scanner. Communications with the device are done by reading and setting registers in the chip. That's fairly straightforward, or at least it would be if I could figure out how to do that from code. That's the next step, turning on the lamp, or moving the carriage, or sensing a button press or something.

After that, I get to the really fun part. Calibration. You'd think that you just have to tell the scanner to give you an image of what's on the page, right? Not exactly. You first have to calibrate the scanner by taking readings of a known image, like a strip of black or white that's hidden inside the scanner. Once you do that, you have to the calculate a whole bunch of stuff with equations that take me back to my calc classes, and then program the scanner with the values derived from those calculations.

Sounds like fun huh?

Comments

( 1 comment — Leave a comment )
brad
Dec. 5th, 2003 10:48 am (UTC)
Back in the old days, hardware did work and you got technical specs with the product when you bought it. (I wrote a printer driver for my Apple II because the specs came with it....) Now it's all driven by software, hardware is dumb, and specs are impossible to find.
( 1 comment — Leave a comment )