ethernet

ethernet

Bit-banging Ethernet on an ATTiny85

1d ago
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Description

So, I found a really terrible way of getting my ATTiny85 to send ethernet packets. No, like REALLY terrible. If you aren't cringing when you watch this video, you're not an engineer. NOTE: The reason this is so dangerous is because some POE switches are wired to be "always on" on the 48V rail. That means if you ground your AVR, it will have 48V going into its inputs which may end VERY badly both for the AVR and potentially even be hazardous to any nearby humans. An AVR runs at 20 MHz, you can output a port one time every clock cycle. By doing that you can create differential signaling at 10 MHz, which is perfect for 10Base-T Ethernet! I am sure this violates the 802.3 standard six ways to sunday. Check out my repo on github: https://github.com/cnlohr/ethertiny