Iris CTF 2024
Sir Scope [280 pts]
This circuit used to write out the flag using an array of 8 LEDs, but the LEDs are all burnt out now.
sir-scope.tar.gz
This one was actually a relatively simple challenge. Although intimidating, the gist is this:
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The yellow represents binary, with the higher states being 1 and the lower states being 0.
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Longer sections represent strings of 0s or 1s, depending if its a high/low state. It can be pretty easily eye-balled.
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The purple is basically a separator between characters. Additionally, it means that whatever yellow is directly above the purple does not count.
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The blue is probably(?) hinting towards the idea that there were 8 binary digits in each character.
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Each 8-bit binary string is actually the reverse of the correct binary
After realizing all of this through testing on the first few characters, I just spent ~20 minutes brute-forcing the flag using Photopea to make things easier and an online converter.
irisctf{0sc1llosc0pes_r_gr8_t00ls_2_hav3}