HP 110 "garbage" on screen

[Jeff_Birt]

(05-10-2023 08:49 PM)dave-in-kc Wrote:  I replaced those two caps on the display board but don't see any difference. I tested the whole keyboard and attached a photo. I pressed each character 2 times. The numbers and special characters seem to work fine but not the letters.

Any thoughts before I slap it back together?

This sort of looks like a stuck bit problem. Presuming they used standard ASCII encoding for characters the alpha characters start at $40 (with @ symbol, then $41 is A) and continue through $7F (actually $7B-$7F are { | } ! ).

If you were to type 'a' ($61) and bit 6 stayed low you would get $21 which is '!'. This does not look exactly like what is showing up on your LCD but perhaps something similar.