It's been going on 3 weeks now trying to communicate with an external device using SPI Mode 3 and the ASF SPI routines. I have studied the datasheets of both the processor and the external ADC, searched the web and this forum, started a forum discussion here that Rx'd 0 responses and entered tech requests at both Microchip/Atmel and Analog Devices.
Should I give up on the ASF solution and simply bit bang the SPI interface? The ASF solution showed much promise since I could, theoretically, communicate with several different SPI devices using Variable Peripheral Select Mode and also changing the SPI Mode to suit the various devices.
Comms look good on a logic analyzer, but are not Rx'd into the buffer consistently or in the order in which I see them on the logic analyzer.
I would appreciate any help at all, suggestions and the like from others who have dealt with SPI on the SAM4S device.