OK, got sidetracked a bit back in March picking up my Amateur Radio General Class license and being pulled into a few other side projects.  But the Firefly project will continue.  Next up will be a proper Interrupt Mode 2 handler for the serial console.  Right now everything is polled, which is not going to work very well once I add the planned mass storage and get into filesystem boggery.

For now, first blog entry is to announce that all source code is publicly available (in a better form) on GitHub:

Firefly Boot ROM and Monitor

The code is 

• Tested to the extent that I have "worked on that area" of the board
• Meant to be efficient where possible and practical but academic perfection was not allowed to get in the way of what I needed to do -- e.g., plenty of areas exist as "rainy-day" projects to come back and optimize
• Mostly mine in authorship but several snippets were adapted and leveraged from other sources, the works of Lance Leventhal being a regular Go-To
• Written in a style and within the constraints of tools appropriate to the era.  At some point I plan to get CP/M running on the board and migrate maintenance and development to legacy tools.  So that's why labels are short and cryptic.
• Yours to use as you see fit

Enjoy.  More updates soon (I hope).

Bill