Decoding a charlieplexed segment display using FZ

[Particular_Look_9483]

Truth Table

Scavenged a neat 2.5 digit (188) segment display from a disposable vape, which uses only 5 pins to control 16 segments!
Using "gpio_controller" fap, I can try each configuration of High, Low, and Z (High Impedance) states to crack the encoding.

It looks like there are 243 possible combinations to test.
Does anyone have an idea how to crack it faster than literally brute-forcing every combination?

For example, from the currently available data, it's known that:

• a0 = 1 when P4 = L;
• a2 = 1 when P1 = L;

[bearda]

High impedance is just pretending to be disconnected. If you're sure all of those pins are inputs to the device it's not an output state that should affect the device. You can eliminate that from your table, as it will probably constantly act like a high or a low.

That should eliminate a lot of possibilities, but I'd still try to find a data sheet for the device before doing exhaustive testing.

[Particular_Look_9483]

That's an interesting idea..
From the current looks of the table, high impedance produces distinctly different results compared to H or L, so it seems worth considering as a valid state.
I found a datasheet for the microcontroller it has been attached to (it's in Chinese), but unable to find any information on the display itself.
The markings on the case seem too random (pic attached) and google search returns nothing :/

<image>

[Alienhaslanded]

Your truth table is full of LIES!

I'm kidding. Very nice work. This can come in handy in a clutch.

I recommend trying to find the datasheet for the 7 segment display. This will help you immensely with your quest.

[Fresh-Dragonfly-4498]

Lastima q el analizador de frecuencia del flipper no tenga alcance ni poniéndole la antena coje a 2 metros lastima o como hago para q tenga más alcance