Spark Fun CAN Bus Read/Write Demo

Hi,

I have obtained two arduinos and two Spark Fun Can Bus Shields. I am attempting to use the CAN_Write_Demo on one and the CAN_Read_Demo on the other. I have connected CANH, CANL, and GND together through the header pins between the two arduinos.

I have used an oscilloscope to see an CAN signal coming off of the “write” arduino.

However, when I open the serial monitor for the port that is connected to the “read” arduino I am unable to see any incoming messages. Shouldn’t these two example projects work as-is when loaded up and connected? I just don’t understand why these example projects aren’t talking to each other.

I am using a knock-off arduino board… the OSEPP-UNO-04 but I don’t think that should change anything.

Any help is appreciated!