The Thermo Plug prototype has been updated to the final version:
This plug supports either a thermocouple, an NTC, or a 1-wire temp sensor on the AIO line, and either a buzzer or a relay on the DIO line. It does not use I2C.
The connections of the AD597 thermocouple readout chip are now correct, and there’s a new 4.7 kΩ pull-up resistor option when using the 1-wire interface.
I’m still looking for a good way to attach the K-type thermocouple (soldering is not a good option with those metals), and am considering adding this plug as kit with AD597, thermocouple, buzzer, and the rest of the components to the shop. This is the combination I’m using in my reflow oven / grill controller. The bare pcb is already available.