Denso BHT-100BW-CE User Manual page 93

If the IrDA interface test ends abnormally:
If the test ends due to a timeout error, the tested slave BHT beeps
three times and displays the screen as shown at left.
This sample screen shows that an error has occurred at 9600 bps.
If the test ends due to mismatch between the sent data and received
data, the tested slave BHT beeps three times and displays the screen
as shown at left.
This sample screen shows that the received data is 255 although data
43 has been sent at 9600 bps.
80