VFD Driver walking-one test

I ran my walking-one test on the Vacuum Fluorescent Display drivers. Initially I had some confusion because I'd forgotten that the VFD mounts on the bottom (keypad) side of this board, rather than the top (component) side as with my VFD driver test board. Thus the ones walked from the right side of the board as I look at it, rather than from the left as I'd intended. But the +30V boost regulator and all of the drivers are working as planned.

With this test configuration loaded I measured the supply current. While supplying 7.5V the board draws about 36 mA, and about 52 mA at 5V. That's about 270 mW, which is in the range I expected to see.

I'm not sure what I'm going to work on next and I may take a little break. I think the next thing on the agenda will be to get the external interface working. Since I lack the Adept Expansion interface I used with the iCEblink, I'm thinking this will be the primary way I'll interact with the board during testing. Maybe I'll take a peek at the PicoBlaze CPU core as a way to drive the testing.

After that I should probably test the Flash ROM interface a bit more thoroughly. While the default 1-bit interface appears quite stable, I should test the 4-bit interface and faster clock rates. And I really should and capture a picture of the CCLK line waveform using my active 'scope probe.