Re: undefined reference issue
A colleague pointed out the issue to me. I am using Harmony 3, moving over from a program that worked under Harmony 2. In any case, the prototypes appearing in the drv_spi.h files have no corresponding function in the drv_spi.c file. This involves functions DRV_SPI_TransferStatusGet , DRV_SPI_WriteTransferAdd, DRV_SPI_ReadTransferAdd.
Supposedly, you need to change the SPI driver setting to asynchronous, and the functions are generated in the drv_spi.c file. I can't say that I totally understand this, in the conventional use of the term synchronous, but this has to do with blocking and non-blocking functions, and with the spi driver listed as synchronous, those functions were removed.