3 ms·

I wrote a firmware that lets me turn any attiny into a gpio-to-i2c and supports in-place-upgrade also over i2c. Now I have up to 20 extra gpio for 0.5$ or so.

I wrote a firmware that lets me turn any attiny into a gpio-to-i2c and supports in-place-upgrade also over i2c. Now I have up to 20 extra gpio for 0.5$ or so. This is not very hard.

foldr 8y ago
The thing with this kind of setup is that it almost always works out cheaper to just buy a microcontroller with more pins. For example, you can easily get hold of 48 pin Cortex M0 parts for under $1.