Yesterday evening I remembered that I had taken a bin log and added some special debug to the firmware in advance. I reached out of bed and pulled up the computer and opened the log, a glorious sight shone back at me. This morning I tidied up the ULV settings so it made sense and got this:

Which I eventually turned into some code after burning a lot of time on my good friend Sean and my good wife Isabel. Tonight I headed down to the shop and tried it, and it didn't work. I have now (probably) fixed it, and will try again in the morning after breakfast. Once I have sync and RPM I will try to wire up some coils and get some ignition happening. Then it's time to use a timing light to dial in the offset. Once that's nailed it's time to run the thing! First things first, though.