Question - Issue maybe for the documentation - Pins used by WifiNINA #302
Description
I'm working on a custom board using the u-blox NINA-W102 module (like the one on the Arduino Nano 33 IoT) and only want to use the WiFi features (Access Point, web server) and support firmware updates via the Arduino WiFiNINA library. Bluetooth is not needed, and I’m not interested in debug output or advanced features.
From the Arduino schematic, I see several NINA GPIOs are connected beyond the core SPI interface – including GPIO1/3 (labeled NINA_PROG_TX/RX), GPIO20/21 (UART), GPIO22/23 (ACK/BUSY), and GPIO35. However, in the actual use case, it seems like only SPI + CS + RESET (GPIO12, 13, 14, 5, 31) are strictly required.
Can anyone confirm which pins are truly necessary for reliable WiFi operation and firmware updating? And why are the other GPIOs connected on the official board if they are unused in this context?
Any insight from those who’ve built custom designs or worked with alternative firmware would be appreciated!
Additional context
Also posted at arduino/nina-fw#119