There's a floppy drive hidden beneath a flap on the top. I have a policy of checking, cleaning and servicing any and all floppy drives in my machines.
With all the sud that came off the CRT screen, I was expecting a lot more dirt. Basically clean.

It's a Panasonic JU-455-5 double sided double density drive, so 360kB formatted.

The controller board lives directly underneath the drive. It's got a uPD765 floppy drive controller, a
uPD8257 DMA Controller, and a uPB9201 floppy disk interface controller, flanked by 8x8K of static RAM.
Interesting design to have extra RAM on here.

I/O options. The RS232 needs a sex change

Let's go

This thing has three display modes for the captured data. Timing, hex and this weird graph mode. In hex the 8 byte (64 input lines) that are captured by the two installed acquisition boards are displayed as four 16 bit words.

Pressing the I/O key brings up this overlay menu, from which you can dump the current memory contents to serial.
Man, 9600 bauds is slow

This thing is so cool. Sadly my phone fails to capture the true color of the phosphorus