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In reply to: Apollo 11 Guidance Computer (AGC) vs USB-C Chargers

I was responsible for the overall firmware for Structure Sensor. It used USB charger detection present on most USB chargers at that time - some resistor network between the USB D+ / D- signals. There was no digital communication. The firmware portion was implemented by Evan Fletcher and I think he reported it was easy to do. That was 2012-2013. Now in 2020 USB-C is here. Many USB chargers have a microcontroller with a CPU. Some are less capable than the Apollo 11 Guidance Computer. Some are more capable than the Apollo 11 Guidance Computer. Most of them with at least ~10x faster clock speed. USB-C Power Delivery solves problems and gives us new capabilities. But it is another step toward increasing complexity. It is another firmware and chip to handle during manufacturing. I don’t have an alternate proposal for power delivery that:

Weird discovery of the day: if my USB C dongle thing is plugged into the rear USB C port on my work laptop (a MacBook Pro w/escape key), and my wireless keyboard’s USB receiver is plugged into the dongle I notice terrible latency while typing. If, however, the dongle is plugged into the forward port? No more latency! I mentioned this to a coworker with the exact same computer. They’ve noticed the same behavior, but flipped 🤷‍♂️