# WifiNINA Driver

This package provides a driver to use a separate connected WiFi processor ESP32 for TCP/UDP communication.

The way this driver works is by using the SPI interface of your microcontroller to communicate with the WiFi chip using the Arduino SPI command set.

## Using the WiFiNINA Driver

For information on how to use this driver, please take a look at the examples located in the [examples/wifinina](../examples/wifinina) directory.

## nina-fw Firmware

**PLEASE NOTE: New Arduino Nano33 IoT boards most likely already have a recent version of the nina-fw firmware pre-installed, so you should not need to install the firmware yourself.**

In order to use this driver, you must have the nina-fw firmware installed on the ESP32 chip. If it is already installed, you can just use it. You do not need to flash the firmware again.

### Installing esptool to flash nina-fw firmware

In order to flash the firmware, you need to use Python to install the `esptool` package.

```shell
pip install esptool
```

Once you have installed `esptool` you can follow the correct procedure for flashing your board.

### Updating the Arduino Nano33 IoT

In the `updater` directory we have a precompiled binary of the "passthrough" code you will need to flash first, in order to update the ESP32 co-processor on your board.

This is what needs to be done. There is also a bash script that performs the same steps also located in the `updater` directory.

```shell
mkdir -p ../build

# reset board into bootloader mode using 1200 baud
stty -F /dev/ttyACM0 ispeed 1200 ospeed 1200

# flash the passthru binary to the SAMD21 using bossac
# code from https://github.com/arduino-libraries/WiFiNINA/blob/master/examples/Tools/SerialNINAPassthrough/SerialNINAPassthrough.ino
bossac -d -i -e -w -v -R --port=/dev/ttyACM0 --offset=0x2000 ./SerialNINAPassthrough.ino.nano_33_iot.bin

# download the nina-fw binary
wget -P ../build/ https://github.com/arduino/nina-fw/releases/download/1.4.5/NINA_W102-v1.4.5.bin 

# flash the nina-fw binary to the ESP32 using esptool
esptool --port /dev/ttyACM0 --before default_reset --baud 115200 write_flash 0 ../build/NINA_W102-v1.4.5.bin
```

You only need to do this one time, and then the correct nina-fw firmware will be on the NINA ESP32 chip, and you can just flash the Arduino Nano33 IoT board using TinyGo.