What is the Altera SPI name convention?

In Qsys, if you've named your SPI peripheral 'spi_1_external' then it will generate a set of names as follows:

SPI_CLK_from_the_spi_1_external

SPI_CS_n_from_the_spi_1_external

SPI_IN_to_the_spi_1_external

SPI_OUT_from_the_spi_1_external

These can be connected up to 'SCLK', 'SYNC', 'SDI' & 'SDO' respectively on the AD5681R. You will have to deal with 'LDAC' separately. However, you do have the option to tie this LOW in which case the DAC will update whenever new data is written.

If your Qsys modue is also your top level design then you will be stuck with these names. However, if you instantiate your Qsys module in a higher level module (or simply a wrapper) you're free to connect any signal name you like to it. So, you can rename it if that suits you.

Cheers,

Alex