DVM (Digital Voltage Meter) page:

DVM (Digital Voltage Meter) shown above serial communication is initialized by running a series of LabView frames. The first frame shown in the image below searches for all enabled COM ports. If none is found it will return string “No COM port found” and the program will exit using “STOP” command.

selected COM port.

Once the serial communication is established the program requests board ID from the attached Multimeter +.

Multimeter + responds with current Board ID:

void send_board_id(void) {
    send_UART(board_ID);
 return;
}

The board ID is received and program continues to the next step.

I give it 1000 ms delay before the main loop starts running.

The next step is to run the main loop where data gets collected and displayed continuously.

LabView Files Link.