On Tue, May 19, 2009 at 10:52:22AM -0400, Stefan Monnier wrote: > That still doesn't explain why removing one of the two accelerometers is > a good idea. What is the benefit? Why not remove them both? > Is it that all the programs that use the accelerometers (as of now) only > use one of the two? Is it that having two accelerometers introduces > layout difficulties? Is it that there aren't enough interrupt lines on > the SoC to properly support the two accelerometers? ...
I don't think so. We already have both EINT8/GPG0 and EINT16/GPG8 reserved for the second accelerometer, but not connected it to EINT16/GPG8 (R1547 = NC). Last time I counted[1], there wasn't a shortage of interrupt or GPIO pins. [1] http://lists.openmoko.org/pipermail/gta03/2009-April/000074.html If we're really going to mess with the accelerometers, why not move them off the SPI1 bus and onto GPIO pins? We're currently using the bitbanging GPIO_SPI driver anyway. That way, we could keep a GTA01/GTA02 compatible debug connector (because WLAN could use SPI1 instead of SPI0). > I actually have the same question for the audio-amp: why remove it? > But that one is a bit more complicated, because I'm not sure what is > this "audio-amp" anyway (is it the thing that drives the > headphone plug?) It drives either the headphone speakers or the bottom handset speaker, depending on the presence of the headphone plug. It's the LM4853 (U4101 on page 7 of the schematics). IIUC, the GTA03 was going to drive both from the WM8753L sound chip directly as suggested in the WM8753L datasheet. I wanted to compare the output power of the two, but I can't find the exact LM4853 variant we're using. -- Rask Ingemann Lambertsen Danish law requires addresses in e-mail to be logged and stored for a year _______________________________________________ Openmoko community mailing list community@lists.openmoko.org http://lists.openmoko.org/mailman/listinfo/community