* Syntax changes that are non-functional from a synthesis perspective.
There are a few errors that are caught by commercial tools and halt
synthesis, which are handled more gracefully by the open source
tool flow. In housekeeping.v: Some wires declared after they are
used. In housekeeping_spi.v: A non-blocking "=" assignment used
where a blocking "<-" assignment was intended.
* Apply automatic changes to Manifest and README.rst
Co-authored-by: RTimothyEdwards <RTimothyEdwards@users.noreply.github.com>
status) so that between rdstb and wrstb, the SPI signals when it is
about to read or write a byte. The back-door wishbone interface then
stalls the CPU during these periods. That allows the CPU to continue
running while the SPI is being accessed without data collisions and
without having to stall for the entire time CSB is held low.
Because SCK is asynchronous to the clock, rare collisions are still
possible; this is not expected to be an issue but might be worth
investigating.