add tx_only_uart example to readme

README.md

@@ -51,6 +51,30 @@ sudo openFPGALoader --board arty_a7_100t -f target/blinky-out/blinky.bit
 
 Follow the steps above of building the Blinky example, but replace `blinky` with `tx_only_uart`.
 
+View the output using [tio](https://github.com/tio/tio) which you can install in Debian using `apt`.
+
+Find the correct USB device:
+```bash
+sudo tio --list
+```
+
+You want the device with a name like (note the `if01`, `if00` is presumably the JTAG port):
+`/dev/serial/by-id/usb-Digilent_Digilent_USB_Device_210319B4A51E-if01-port0`
+
+Connect to the serial port:
+```bash
+sudo tio -b115200 /dev/serial/by-id/put-your-device-id-here
+```
+
+You'll see (repeating endlessly):
+```text
+Hello World from Fayalite!!!
+Hello World from Fayalite!!!
+Hello World from Fayalite!!!
+```
+
+Press Ctrl+T then `q` to exit tio.
+
 # Funding
 
 ## NLnet Grants