Huawei HarmonyOS Support, Harmony TP Cable2022-11-27         Follow @huaweinewos Tweet to @huaweinewos
How to use factory/boot mode service functions on Huawei devices with HarmonyOS?
Problem: Due to some changes made by Huawei, phones updated to HarmonyOS would not show Huawei USB COM 1.0 serial port after test markup. Without Huawei USB COM 1.0 serial port, Chimera cannot communicate with these devices in factory/bootrom mode.
Solution: You need to use a modified USB cable, we call it “Harmony TP Cable”. If this cable is used, the Huawei USB COM 1.0 serial port can be used and all Chimera factory/boot mode service functions will work on HarmonyOS models.
Harmony TP Cable, How-To:
What do you need:
- 1 pc. 150 Ohm (150 Ω) resistor
- 1 pc. 270 Ohm (270 Ω) resistor
- 1 pc. 1.5 kiloohm (1.5 kΩ) resistor
- 1 standard USB cable
How to make a cable:
- You still need to test the point (this cable will only work if the test point is made)
- Make sure you always connect the cable to the phone first.
- When prompted to disconnect, always make sure to unplug the cable from the computer first.
- You should see Huawei USB COM 1.0 serial port in Windows Device Manager. If you can’t see it, most likely the replaced cable is wrong.
Why do I see unknown device in Windows Device Manager?: You probably connected the cable to your computer first. Please make sure to connect the cable to the phone first.
I have unplugged the cable but I can still see the phone is connected, why?: You probably unplugged the cable from the phone first and not from the computer. Please always make sure to unplug the cable from the computer first.