Desk of Ladyada - STEMMA QT RTS & UPDI Time

We’re back from a break last week, and jumping into some hardware designs we put together before we took last weekend off. Two RTC QT designs - starring our two favorite RTC chips - the DS3231 and the PCF8523! We also started adding UPDI support to the AVR programmer library we use for computer-less programming. Thankfully we are able to use the open source port of pymcuprog from brandanlane: and with a little noodling, have got some data going back and forth. The Great Search - Coin Cell Battery Holder Lead Time Trends For our RTC QT breakouts we want to add a coin cell holder on the back. I like these bent metal ones, they are inexpensive, easy to pick and place or hand solder, and are incredibly durable - they don’t corrode or get loose over time (and if they did you could bend them right back!) Thanks to jepler for pointing out this nifty ’lead time trends’ page over on