“Our ability to interrupt television has been demonstrated.”

Hobby electronics and programming projects: https://codeberg.org/interrupt_tv

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Joined 2 months ago
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Cake day: January 20th, 2026

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  • Ah, sorry, I could have been more clear there. It can do arbitrary mappings between input values and output values. So for each possible 4-bit value, you can pick a different 8-bit value to be output.

    For my case, I’m working with a 7-segment LED display, like the display on a microwave. It’s got 7 LEDs arranged to display a number, plus an 8th LED for a decimal point. Like this:

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    if the ROM is getting 0000 for its input, it should light up all segments of the 7-segment display except for the horizontal one in the center, to display a zero. Then for the 0001 input, it should light up the two vertical segments on the right, leaving the rest dark, to display a one. And so on. Each output bit goes to a particular segment of the display.

    To relate it more directly to programming, it’s like having a 16 byte array. The input gives the array index that you want to access, and the output gives whatever byte is at that index.


  • Oh, that’s cool. I hadn’t heard of slimevr before.

    My use case for the diode ROM board is to take 4 binary input bits (16 possible combinations) and translate them into what segments of a 7-segment LED display should be lit or unlit, in order to display the corresponding hexadecimal digit (0-9, A-F). Like so:

    Diode ROM in use

    It could be used for any other case where you need to convert a 4-bit input into 16 possible 8-bit outputs. In theory you could use them in multiples for more address space, but I forgot to include an enable pin on the board to allow for that. Something to add to the next version.


  • Not programming per se, but I’ve been working on some electronics projects. If you check my profile, there’s two PCB designs that I’ve posted. They’re fairly simple, but I’m working on a larger project that I should be posting relatively soon. Currently I’m just waiting on a shipment of parts, because I didn’t realize I would need XNOR gates.