Update README

README.md

@@ -12,8 +12,127 @@
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-Be sure to have `libudev-dev` installed
+The `uno-r4-wifi-fwuploader-plugin` is a core component of the [arduino-fwuploader](https://github.com/arduino/arduino-fwuploader). The purpose of this plugin is to abstract all the
+business logic needed to update firmware and certificates for the [uno r4 wifi](https://docs.arduino.cc/hardware/uno-r4-wifi) board.
 
-### Ubuntu:
+## How to contribute
+
+Contributions are welcome!
+
+:sparkles: Thanks to all our [contributors]! :sparkles:
+
+### Requirements
+
+1. [Go](https://go.dev/) version 1.20 or later
+1. [Task](https://taskfile.dev/) to help you run the most common tasks from the command line
+1. The [uno r4 wifi](https://docs.arduino.cc/hardware/uno-r4-wifi) board to test the core parts.
+
+## Development
+
+When running only the plugin without the fwuploader,  the required tools are downloaded by the fwuploader. If you run only the plugin, you must provide them by hand.
+Therefore be sure to place the `espflash` and `bossac` binaries in the correct folders like the following:
+
+```bash
+.
+├── bossac
+│   └── 1.9.1-arduino5
+│       └── bossac
+├── espflash
+│   └── 2.0.0
+│       └── espflash
+└── uno-r4-wifi-fwuploader-plugin_linux_amd64
+    └── bin
+        └── uno-r4-wifi-fwuploader-plugin
+```
+
+**Commands**
+
+- `uno-r4-wifi-fwuploader-plugin cert flash -p /dev/ttyACM0 ./certificate/testdata/portenta.pem`
+- `uno-r4-wifi-fwuploader-plugin firmware get-version -p /dev/ttyACM0`
+- `uno-r4-wifi-fwuploader-plugin firmware flash -p /dev/ttyACM0 ~/Documents/fw0.2.0.bin`
+
+
+## Known problems:
+
+### Espflash panic `UnknownModel`
+
+On some arm64 Linux distros, version 2.0.0 of [espflash](https://github.com/esp-rs/espflash/) might panic with the following error:
+
+```
+Error:   × Main thread panicked.
+  ├─▶ at espflash/src/interface.rs:70:33
+  ╰─▶ called `Result::unwrap()` on an `Err` value: UnknownModel
+  help: set the `RUST_BACKTRACE=1` environment variable to display a
+        backtrace.
+```
+
+### The esp32 module does not go into download mode
+
+On Linux, the uno r4 must be plugged into a **hub usb** to make the flash process work. Otherwise, it won’t be able to reboot in download mode.
+
+```bash
+$ arduino-fwuploader firmware flash -b arduino:renesas_uno:unor4wifi -a /dev/ttyACM0 -v --log-level debug
+
+Done in 0.001 seconds
+Write 46588 bytes to flash (12 pages)
+[==============================] 100% (12/12 pages)
+Done in 3.106 seconds
+
+Waiting to flash the binary...
+time=2023-07-18T14:50:10.492+02:00 level=INFO msg="getting firmware version"
+time=2023-07-18T14:50:10.509+02:00 level=INFO msg="firmware version is > 0.1.0 using sketch"
+time=2023-07-18T14:50:10.511+02:00 level=INFO msg="check if serial port has changed"
+[2023-07-18T12:50:20Z INFO ] 🚀 A new version of espflash is available: v2.0.1
+[2023-07-18T12:50:20Z INFO ] Serial port: '/dev/ttyACM0'
+[2023-07-18T12:50:20Z INFO ] Connecting...
+[2023-07-18T12:50:20Z INFO ] Unable to connect, retrying with extra delay...
+[2023-07-18T12:50:21Z INFO ] Unable to connect, retrying with default delay...
+[2023-07-18T12:50:21Z INFO ] Unable to connect, retrying with extra delay...
+[2023-07-18T12:50:21Z INFO ] Unable to connect, retrying with default delay...
+[2023-07-18T12:50:21Z INFO ] Unable to connect, retrying with extra delay...
+[2023-07-18T12:50:21Z INFO ] Unable to connect, retrying with default delay...
+[2023-07-18T12:50:21Z INFO ] Unable to connect, retrying with extra delay...
+Error: espflash::connection_failed
+
+  × Error while connecting to device
+  ╰─▶ Failed to connect to the device
+  help: Ensure that the device is connected and the reset and boot pins are
+        not being held down
+
+Error: exit status 1
+ERRO[0021] couldn't update firmware: exit status 3
+INFO[0021] Waiting 1 second before retrying...
+INFO[0022] Uploading firmware (try 2 of 9)
+time=2023-07-18T14:50:22.229+02:00 level=INFO msg=upload_command_sketch
+time=2023-07-18T14:50:22.230+02:00 level=INFO msg="sending serial reset"
+Error: reboot mode: upload commands sketch: setting DTR to OFF
+...
+```
+
+### I flashed the certificates, but I am unable to reach the host
+
+The **whole certificate chain** is needed to make it work. Using `-u` flags (ex: `-u www.arduino.cc:443`) won’t work because it
+only downloads the root certificates. The solution is to use only the `-f` flag and provide a pem certificate containing the whole chain.
+
+### My antivirus says that `espflash` is a threat
+
+The binary is not signed [#348](https://github.com/esp-rs/espflash/issues/348), and some antiviruses might complain. If still doubtful, https://github.com/esp-rs/espflash is open source,
+and it's possible to double-check the md5 hashes of the binary and the source code.
+For more information, you can follow [this](https://forum.arduino.cc/t/radio-module-firmware-version-0-2-0-is-now-available/1147361/11) forum thread.
+
+## Security
+
+If you think you found a vulnerability or other security-related bug in the uno-r4-wifi-fwuploader-plugin, please read our [security
+policy] and report the bug to our Security Team 🛡️ Thank you!
+
+e-mail contact: [email protected]
+
+## License
+
+uno-r4-wifi-fwuploader-plugin is licensed under the [AGPL 3.0](LICENSE.txt) license.
+
+You can be released from the requirements of the above license by purchasing a commercial license. Buying such a license
+is mandatory if you want to modify or otherwise use the software for commercial activities involving the Arduino
+software without disclosing the source code of your own applications. To purchase a commercial license, send an email to
+[email protected]
 
-`sudo apt install libudev-dev`