Pi pin configuration Q

If I configure my pins as in this diagram:

input is low when output is low, input is high when output is high|690x361

Do I need to set my N-R pins as pull up/down or none?



Also, is this the section where I can get someone with experience to check out my breadboard schematic so I don't fry my pi?

The 10k (and 1k) resistors act as a pull down - so you don't need either pull up nor down.
That schematic looks fine, or did you mean something else. ?

Something else. I've got a breadboard laid out with 5 pin functions that I'd like to get checked out. I've been testing them (minus pi!) with a VOM + USB 3v3 PS and having some issues. I posted a couple days ago in "general" and got no hits, was wondering if "hardware" might be better.

I can't test the motor direction switch yet (pins 32, 36) as my current stash of optos are bi-directional, waiting on "unis".

Output to cycle (pin 22) works (outputs as switch, completes circuit).

Verify closed works, meter on grd, (pin 40 socket) goes from 0 to 3v3 when verify open sees power.

Verify open shows 0v between grd and pin 38 (socket) when input is 0. When verify open input is 3v3, pin output goes to 0.015v. If I switch my meter lead to 3v3, the readings are 3v3 when input is 0, then it goes 3v46 when 3v3 is applied. I've swapped optos, same result...


Well, it's on me. I used a generic chip diagram instead of the IL755-specific one. Seems the output emitters are the outboard pins while the collectors are inboard instead of staggered. Fixed!


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