PCB devboard the size of a USB-C plug

github.com

81 points

zachlatta

a day ago


18 comments

stephen_g 10 minutes ago

Title is inaccurate, it's really designed to be about the size of a USB-C receptacle , the plug is the other side (in this case the part of the cable that plugs in to this board)

george_max 3 hours ago

Very nice. I am wondering -- why have a devboard this small?

  • rolph 2 hours ago

    ...trust me this is the best USB cord ever try it out for free, ill sell you some cheap if you get a couple friends to buy some.

    https://shop.hak5.org/products/omg-cable

    https://phreakboutique.com/blogs/tutorials/using-your-new-ev...

    thats how the grift starts...

    • rkagerer 2 hours ago

      That's it, I'm going back to parallel port cables for everything now.

      • jasongill an hour ago
        2 more

        The parallel port (at least in it's later implementations) actually supports DMA - I'm sure that data exfiltration via the parallel port is hard, but probably not impossible...

        Nothing is safe, unfortunately!

        • toast0 36 minutes ago

          The parallel port controller can DMA, that lets the driver tell the port hey, send this buffer out to the port and let me know or read this many bytes into this buffer and let me know. It's not peripheral controlled DMA like with firewire or PCI.

          You can absolutely exfiltrate data via the parallel port... that's why you attach printers or zip disks... it's just that it needs host participation.

chrisallick 3 hours ago

This looks awesome, I'd love to get one. Question, what's the advantage over something like the ESP32C3 and the like? Just even smaller?

  • rkagerer 3 hours ago

    If it helps, I've used earlier Atmel AVR chips, as well as the ESP32-S3.

    8-bit AVR is an extremely clean, relatively simple instruction set that can be viably hand-coded. It's fairly straightforward to calculate the exact number of cycles your code will use, which is handy for applications requiring deterministic timing and for knowing worst-case execution time of interrupt handlers.

    If the C3 instruction set is anything like the S3, I'm willing to bet it's not as straightforward.

    Atmel also tends to do a better job of their documentation. I've lost count of how many confirmed errata I've reported to Espressif, and the time (and steam) I lost troubleshooting them in the first place.

    I like the S3, and it's heaps powerful, but for small projects that don't need advanced peripherals like Wifi, DMA, etc. I can envision that AVR as being a fine choice.

    • girvo 2 hours ago

      > If the C3 instruction set is anything like the S3, I'm willing to bet it's not as straightforward.

      Its not, not really anyway. The Xtensa LX7 in the S3 is very weird, though also quite fun to play with. The C3 is RISC-V

      • rkagerer 2 hours ago

        Thanks for correcting me. Are there any good, small "Hello World" examples of RISC-V programming with the C3 you can point me to? I'd love to get a sense of how it compares in practice.

  • throwaway81523 3 hours ago

    It's a much less fancy cpu that's very small. No wireless. Lower powered I would expect. But it's an MCU with something like 16KB of flash and 2KB of ram if I remember right. The analog stuff on it is supposed to be pretty good. The Anduril flashlight firmware (toykeeper.net/anduril) is a somewhat popular application that can run on it.

    • tgsovlerkhgsel 3 hours ago

      > Lower powered I would expect

      With the right software, ESP32 can be incredibly low power. Like "months on 3xAA batteries" for watching a pin with the ultra low power subsystem and then occasionally waking up and making a HTTPS call over WiFi.

tl2do 3 hours ago

I'm interested in this too. I've been using STM32 NUCLEO boards, which are cheap and capable, but even the smallest ones are noticeably larger than this. I'd love to see an STM32 version of this project.

motorducky an hour ago

That thing is sexxxy. Very nice board, beautiful documentation.