Ew, pretty busy #weekend, but had some time for yet another iteration of my serial/parallel ISA card.
I replaced the two 16C550 with a single 16C554 (for a total of 4 serial ports!) and added circuitry for an expansion ROM (going to save me an ISA slot on a few 286/386 machines).

Will ponder on this one a bit, and if everything looks fine I'll send it for production in a week! #retrocomputing #homebrewcomputing