I have been trying to utilize the SoftwareSPI functionality in SdFatLib with the Arduino Zero to no avail. I have downloaded the latest beta version (as of 8/16/15) with no luck. If I rewire the board to accommodate the includes SPI port on the board the standard SD library works fine, but I need to utilize other pins for my project. In particular, the project utilizes the specific MOSI, MISO, SCK and SS pins (10-13) as outlined in the SoftwareSPI example code.
Is there a timing or setting issue that I'm missing?
After further research I discovered the SERCOM components of the SAM D processors. I changed the SERCOM settings for the SPI ports and all the code written for the original SPI port was re-routed to the new pins. Thus it appears that the Zero may alleviate the need for the Software SPI component for the Cortex M0 processors. Your efforts would seem to be wasted in addressing this matter for the Zero platform.
I truly appreciate your insights and am grateful to you for providing the community with a remarkably valuable tool to manage SD cards on these little platforms!
All modern ARM development boards should have several SPI ports so software SPI is not needed. Arduino ARM designs are poor so I don't use their ARM boards for my projects.
Here is a typical ARM board, the Seeed Arch Max for $39.95.
Here are features and number of interfaces. Note three SPI and a separate SDIO if you want high speed SD access.
ARM Cortex-M4 MCU with FPU at 168MHz, 512KB Flash, 192 KB RAM