Rask Ingemann Lambertsen wrote: > Figure 22-2 of the SC32442B manual shows SPI data changing on SPI clock > edges.
Yeah, I wouldn't be at all surprised if the "disabled" accelerometer misfired every once in a while. This kind of design is practically begging for it ... > The direction of shift doesn't matter so much if you send software SPI > clock pulses, just ask the card for e.g. firmware revision and discard bits > until the alignment is right. Hmm, I'm not entirely sure, but I think the game starts again for each SDIO transfer. Our main user of fast SPI would be WLAN, which we'll never see in this form again after gta02-core anyway. So I wouldn't put much effort into debugging 2442 SPI, considering that a real product would use a different CPU anyway. E.g., even if we want to stay very close to the gta02-core design, the 2450 would be a much nicer choice than the 2442: http://origin2.samsung.com/global/system/business/semiconductor/product/2008/8/20/401324ptb_s3c2450.pdf > The thing is that the 2442 SPI interface is poorly documented in places. Indeed. Quite a lot about the 2442 looks a bit like a rush job. > Does it mean that gta02-core WLAN SPI is effectively limited to > 66 MHz / 3 = 22 MHz rather than 66 MHz / 2 = 33 MHz? Good point. I guess we just have to try and see what happens :-) - Werner _______________________________________________ gta02-core mailing list [email protected] https://lists.openmoko.org/mailman/listinfo/gta02-core
