This usually indicates a Baud Rate mismatch. Standard baud rates for MPT-II are often 9600 or 115200; ensure this matches in your driver's port settings.
RS-422 requires a different electrical standard, but the driver stack is identical. You may need an RS-422 to USB converter. The driver will be for that converter, not the MPT-II itself. Mpt-ii Driver Download
: The MPT-II has been replaced by the HM-E200 , so finding the original drivers from official sources is becoming more of a challenge. This usually indicates a Baud Rate mismatch
Ensure your specific MPT-II model supports (Standard Bluetooth-only models will not work on iOS). Mpt-ii Driver Download
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