This program demonstrates the Ethernet TX capability on an STM32F407 board connected to an ENC424J600 module via SPI. Once loaded and initialised, a specific ping packet is sent (broadcasted) every 100ms. Such a packet has the following properties:
* Destination MAC Address: ff-ff-ff-ff-ff-ff
* Source MAC Address: 08-60-6e-44-42-95
* Destination IP Address: 192.168.1.231
* Source IP Address: 192.168.1.100
* Frame Length in Bytes: 64
Note that this program uses ITM for logging output.
#### How-to
1. Prepare the Rust and Cargo environment for building and running the program on STM32F4xx Cortex-M platforms.
2. Install [`itm`](https://docs.rs/itm/) on Cargo:
```
cargo install itm
```
If necessary, add your installation location (`~/.cargo/bin` by default) to `$PATH`.
3. Connect your STM32F407 device to the computer. Without changing any code, you may use an STLink V2 debugger.
4. Run OpenOCD with the appropriate configuration files (e.g. `interface/stlink-v2.cfg`, `target/stm32f4x.cfg`).
5. With OpenOCD running, build and run this program:
```
cargo run --release --example=tx_stm32f407 --features=stm32f407
```
Use appropriate GDB commands such as `c` for continuing.
6. On a separate console window, monitor and observe the ITM output, which is located at the same directory as you started OpenOCD:
