We have selected that AtTiny167 for our project. It has the right parameters, such as I2C Master, 16K Flash, 512 SRAM, etc. to do the work we need, and the SOIC20 fits the very limited space we have to place it. We are talking about a very small form factor overall.
Now I'm faced with several problems: what outboard components do I need to make it happy? The plan is to use the internal oscillator, so that drops the crystal oscillator and two capacitors. Of course, the standard bypass capacitor between Vcc and Gnd will be there, and the voltage regulator is not needed because it will be powered by a 3V lithium coin cell. So now the question is, using the Arduino IDE, how to I set up a programming interface to it? How do I program a boot loader in? I have used FTDI and USB interfaces in the past. I am less confident that I have a clue as how to design or use an ISP interface.
I also need an Attiny167 component for Fritzing. A google search was remarkably unrewarding, apparently ignoring the 167 part of the search string and delivering me a ton of Tiny85 projects. No part drawing for the '167 was revealed. Ideally, the SOIC20 physical package will be part of the drawing, but I need a schematic part as well, and will settle for one which is not the same physical package if necessary.
Suggestions on how to proceed would be greatly appreciated. joe