On Thu, Mar 13, 2008 at 6:06 PM, Oliver Ford <[EMAIL PROTECTED]> wrote: > eric miao wrote: > > On Wed, Mar 12, 2008 at 8:43 AM, Oliver Ford <[EMAIL PROTECTED]> wrote: > > >> There is one small thing I still have no clue about, what are the > >> "Alternate Function Selections" MFP_AF0 through MFP_AF7? > >> > > Represents a maximum of 8 possibilities of alternate function for > > a MFP (Multi-Function Pin). > > > > I'm following this much better now. Looking at the dump of the MFP > config windows uses, a lot of things (like the LCD) have pins selected > to the same AF as the Zylonite configuration does. Some others, like the > FFUART, have different pins configured with an AF to do the job, > consistent with alternate configurations you have defined in > mfp-pxa300.h. However, other systems, like the AC97 and MMC2 look like > windows doesn't use any of the configurations in mfp-pxa300.h. Is this a > complete list? If not, is there any way I can get hold of a list of what > the alternate functions do for each pin? >
This is a quite complete list except for some devices we don't yet have a driver for. MFP in win might have slightly different drive strength but the alternate function should be at least same. BTW: windows uses a different and much more complicated framework than Linux does, so there is no strict one-to-one mapping relationship. > The MFP configs windows uses often have bit 15 (MFPR_PULL_SEL) set but > neither of bits 14 or 13 (MFPR_PULLUP_EN or MFPR_PULLDOWN_EN) set. What > exactly does this mean, if anything, as mfp-pxa3xx.h doesn't list it as > a possibility? > The purpose of setting PULL_SEL while leaving PULLUP_EN/PULLDOWN_EN is to override the default pull settings and leave both pull up/down resistors unconnected. I doubt this is necessary for the vast majority of the MFP, but some pins may require such weird setting. A basic observation is that leaving PULL_SEL as zero should work in most cases. > The wireless/bluetooth LED, btw, was being switched off on the way into > linux when the Zylonite config was reconfiguring GPIO3_2 for the keypad. > Windows has GPIO3_2 config'ed to AF0 with DS04X (I'm guessing that most > of the AF0's are 'direct to bit in GPIO registers' config) and GPIO3 > config'ed to AF4 (not sure where that goes). Clearing GPIO bit 3 in > windows turns off the LED but doesn't effect the bluetooth link. I > suspect, assuming that DS04X is just a slightly higher current > availability pin (4mA by any chance?), that this is just wired to the > LED. Either way, I now have complete control over 1 device... the LED. > Good news. The default of a GPIO drive strength is DS03X, which is supposed to work in most cases. Driving a LED directly through a GPIO doesn't look like a good idea, though the MFP can sometime provide more current than what the doc said. > > Thanks for all the help, > > Oliver > -- Cheers - eric _______________________________________________ Haret mailing list [email protected] https://handhelds.org/mailman/listinfo/haret
