Let's assume a master node (esp32) where I need to expand the available GPIO ports.
One solution would be to use multiple "GPIO expanders" using I2C communication.
Another solution would be to use multiple esp32/esp8266 connected each other with I2C or SPI (but honestly i don't see advantages in this, you need, I think, one firmware on each device or the "master" device will be able to access remote GPIOs even on unconfigured firmwares ?)
Any other solution ? Any package allowing I2C/SPI-like communication between nodes, via WiFI ? Would be much better for cabling and PCBs
Other than that, which GPIO expander would you suggest ?
Are tehere any limits on the number of usable ports on a esp8266/esp32 ? In example, can I put 24 220v relays, 10 temperature sensors and so on, by using multiple GPIO expander on a single nodemcu ?