Huzzah – Legible Scope Output

Legible Scope Output

Legible Scope Output

Still an artifact at the top, and I frequently see some dots flash on the screen (not seen in this image), but I’d say I”m almost there.

I had a couple of issues that had to be solved to get to this level.

The big one was that I had inverted the logic for displaying vectors. I had programmed ones in the registers to display lines and zeros to suppress vectors. The problem with that logic was that all the vectors that repositioned the cursor to the next position were enabled with this logic. I had to invert the output and use zeros to turn on vectors. Once I fixed this, I could easily adjust my Tektronix 465 to suppress vectors that were not to be displayed.

The second issue was that my rework instructions were wrong and had pins 1 and 3 swapped on Z3. This kept vector B2 enabled all the time.

Next step is to add the keyboard driver and check the vectors that I have programmed for the other characters and make sure the remaining lines and columns look OK.

One Response to “Huzzah – Legible Scope Output”

  1. Jack Rubin says:

    I think I have an old EICO round-screen scope that would like pretty good with this project. Yours for shipping if you want it (and if I can find it!). Let me know.