Oh yeah, forgot to 'splain:
SS50 bus section
3 - 16K SRAM boards
1 - 6800 (1MHz) CPU card
1 - Single Density Floppy Card
1 - Gimix Video Card
SS30 bus section (in order, left to right)
Microware 6850 card
3- MP-S (6850 card)
A sound card
Microware 6850 card
Clock card
MP-LA card
No idea on it's purpose but it has a one serial for the keyboard, a clock, a sound and video card. So personal computer with a lot of IO? ;-)
So the first serial might be console (I haven't tried yet), 4th serial is modified for TTL serial.