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If you're running Windows 7 or 8 instead of Windows 10, via Google
Chrome won't be able to match devices. You'll need to use the CoolTerm
serial monitor software to read data.
You could open CoolTerm software, click Options, select SerialPort, set
COM port and put baud rate to 115200 (after testing, the baud rate of USB
SerialPort communication on Micro: Bit main board is 115200), click OK,
and Connect. The CoolTerm serial monitor shows the change of
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