JohnSwenson wrote: > How about the AM3874? This is what I was planning on using For Gen2 > since it has all the display stuff builtin. According to the technical > manual the USB system DOES have a hardware scheduler, checking the > details you can turn off packet interrupts if using DMA so it looks like > this might be better. >
This still looks like the more limited hardware: "An interrupt is generated whenever a packet is received from the host and the software may use this interrupt to unload the packet from the FIFO and clear the RXPKTRDY bit in the PERI_RXCSR register (bit 0) in the same way as for a Bulk Rx endpoint. As the interrupt could occur almost any time within a frame(/microframe), depending on when the host has scheduled the transaction, the timing of FIFO unload requests will probably be irregular. If the data sink for the endpoint is going to some external hardware, it may be better to minimize the requirement for additional buffering by waiting until the end of each frame(/microframe) before unloading the FIFO." It may work fine - all I'm saying is that its not EHCI which I suspect needs more gates to implement as there's no need for an interrupt per packet. If you compare the usb section with the usb host port section in the AM3715 reference manual you will see the difference. This looks to have separate host and otg hardware - the host port is ehci/ohci, whereas the otg is the mentor block. Lets see what your Beagle Bone does when you get it and then review. ------------------------------------------------------------------------ Triode's Profile: http://forums.slimdevices.com/member.php?userid=17 View this thread: http://forums.slimdevices.com/showthread.php?t=97881 _______________________________________________ discuss mailing list [email protected] http://lists.slimdevices.com/mailman/listinfo/discuss
