I just went to charge my kitchen scale and it wouldn’t work until I dug out a USB-A -> C cable and plugged it into my desktop…
It just reminded me of how many devices like that I have. This scale, my wife’s sound torc, some car jumperstarters, and I think a one or two more…
I assume it’s because they just slap a usbc port on a dumb 5v circuit that doesn’t have a power negotiation controller. So the cable and the charger cant figure out the power needs of the device are and just never send any.
Bro have you SEEN the price of resistors lately?
……cuz I haven’t and I assume it’s fractions of a penny per.
I worked on an embedded product, on prototype there were pullup resistors on the RX/TX lines we used to plug a USB FTDI to do some debug. At manufacture they removed them, it created a floating RX that sometimes injected character that broke uboot…
I love stories from hardware / embedded design. Reminds me that black magic is real, and it’s a miracle any of this works.
What is completely incredible, is that there is some simple embedded devices, be it a thermostat, dishwasher, etc, that sold thousands/millions of units, and the firmware is done by one guy, a simple developer, and when it works, it is not touched again.
A fraction of a penny per? Have you seen superman? Office space? How do you think millionaires are made?