Implement SPI through to the CPU.
Correct name is SIWU not SIWA.
Simplify the stretch logic.
Uncomment the cpu ssi pins.
A read delay implementation that doesn't trip the magic downconverter
corruption.
Fix ir overrun flag.
Use an LED to indicate out-of-whack strobes.
Run the read-delay counter from state idle.  This replaces the prefer-tx flag.
Trivial clean-up
Make the read delay configurable.
Set the xmit_last flag for the burst sample.
Trivial clean-ups.
Add the ssi test - won't work without external clock to cpu...
Don't frig the transmit mode in usb flush...
spiflash programming now uses both buffers.
Use x/y coordinates instead of (mislabeled) i/q coords.
Trivial tweaks.