On Friday 21 January 2005 00:51, John-Mark Gurney wrote: > Milan Obuch wrote this message on Wed, Jan 19, 2005 at 10:00 +0100: > > [skip] > > Great, could we cooperate? > > Sure, though Joerg Wunsch has been doing work w/ I2C more recently than > me, so you might want to drop him an email. >
Is he on this list? I have no other idea how coould I reach him. > > I know there are two modes - bit banging software i2c bus and real > > hardware controller. Which one would be easier to begin with? With geode, > > both are possible. Pins designed for ACCESS.bus (at least the second, > > there are two buses integrated) can be used as GPIO pins. > > The hardware I worked on was bit banging only, so I used that interface > and it was surprisingly easy, since you just define an interface that > will get called by the i2c bus to do the necessary toggling... Of course > this is more cpu intensive since it requires timing and other things > like that.. > Maybe I will try to make bit banged version first. Just when I find all the subtle details necessary to toggle pins... > Take a look at sys/dev/iicbus/iic*_if.m. Those are the two different > programming interfaces. You of course just need to do one of the two... > I did. Actually first I must figure how this all contributes to total picture... I am on my way. I must first know the hardware part, which is not that easy on the first stage, but I am reading through specs, some examples, mostly in assembly. I am doing my homework :) [skip] > > You can take a look at lpbb for a simple example of the bit banging > interface... sys/dev/ppbus/lpbb.c The other controllers also implement > iicbus directly.. You can look at the modules/i2c/contollers/*/Makefile > to see who uses iicbus_if.h to see examples that implement it.. > On the other side - what is sys/dev/pcf directory for? I do not see those files referenced elsewhere... Other than that, device pcf looks like the best candidate to work with. I would like to use integrated controller, naturally. Regards, Milan N. B. No need to send cc: to me, I am subscribed. _______________________________________________ freebsd-hackers@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-hackers To unsubscribe, send any mail to "[EMAIL PROTECTED]"
