How to read the serial data from a ATMEGA8 on a PC using Arduino? I want to check if a device is working or not. It is a custom made PCB with a Atmega8. It was given to me along with the AVR code. How do I read the data that it sends on my laptop using a arduino, preferably a Arduino Uno?

I tried connecting the output UART pin to the Rx of the arduino, and then provided the common ground. Then I opened serial monitor on my laptop but I a m not getting anything. Is it because the PCB is damaged or am I doing it wrong?

I have the AVR code which was burned on the IC, so I can provide you with more information if you need.
If you connect the TX pin on your device to the 'TX' pin on the Arduino, then load a sketch such as 'blink' that won't initialize the Arduino's own UART, you can use the Arduino's onboard USB-UART adapter to talk to your device.