3 ms·
> shift register required for ESP8266 Why? A D1 Mini has 8 Digital I/O ports that could drive a 3.3.v relay module.
by cptskippy 4y ago
> shift register required for ESP8266
Why? A D1 Mini has 8 Digital I/O ports that could drive a 3.3.v relay module.
- tamu_nerd 4y agoNot sure, I didn't try, but using one was a good excuse to learn how. The blog post suggests that despite there being 8 they're not all suitable for use (maybe due to high on boot or something)
- cptskippy 4y agoAh... that makes sense. It looks like IO0 needs to be pulled high to boot. Still looks like you could redefine RX to a GPIO and still have 8 if you didn't need serial input. I vaguely remember running into this issue with some load cell AMPs. A Shift Register or IO Expander seem like the more interesting and less frustrating route. I'd probably end up using an ESP01 and i2c IO Expander because I'm a masochist and love trying to squeeze as much as I can out of the ESP01.