This a very simple and cheap project that turns into a very helpful and powerful tool. It uses and Arduino UNO and a 2.4" TFT LCD Shield with TouchScreen.

It has 4 connection lines:

• +5v
• Serial 1 (White)
• Serial 2 (Green)
• GND

It takes power from the device to inspect so no battery is needed.

It's configure to work in landscape mode, but it could be easily changed to portrait mode in order to have more rows to inspect.

For a better visualization, the serial input is truncated so it would fit on a single row (that also a reason why it's designed in landscape mode).

After the screen is filled it starts a new blank screen. And this was a little annoying when a fast communication was inspected. So this is where I decided to add an SD Card for logging, and as the TFT Shield has one, it was a perfect match.

I think there are a lot of ways to improve this project, one could be a navigation on the data logged, using the touch screen and enabling of disabling the auto-scrolling. But I was not having luck with the touch interface, it just won't work.

Also it was not done with the Adafruit library because I was testing another lib built for this specific LCD Model, I think migrating to the Adafruit one will make this more flexible.

Right now I'm not using it only as a monitor but as a logger as well. I leave it hooked to the device so I can go there and monitor the communication and also extract the SD and analyze the log.