Second development card
This started out badly. I decided to make use of some QFP 68030s I'd bought since they took up less space and I wasn't trying to thrash them to high speeds yet. I still hadn't added an external oscillator as was aiming only for 16MHz operation from the main clock.
Rev2.
Only one small problem with this board: the 68030 QFP package has pin 1 at the top centre; my footprint has pin one at the top left corner.
All my routeing was immaculate, but the bloody pins weren't where the pads were. A touch of the Eric Morecambe at the piano to this one.
Rev 2b.
Rev 2b saw a reversion to the PGA 030 and I decided I'd add space for an external oscillator directly onto the board. You'll also notice the upgrade to the 68030 CPU. A full, known good, 50MHz one fresh from the Exxos store, to rule out any issues on that front.
Dev work narrative to come
This was the breakthrough board. I finally got an external 030 to drive the Falcon. It was able to initialise the graphics and partially boot the diagnostic cartridge.
insert dev work narrative here
A bodge wire or two later, this model gets fully up and running and able to think about Alt-RAM.
insert more dev work narrative here
This is the revision that has managed to get to almost full functionality including booting directly from TOS, running at 48MHz and providing 1MB of Alt-RAM. The first real prototype.
This is great -- but it's not what I wanted. I wanted memory first, speed second. 1 megabyte isn't enough. It's time for Revision 3.