USB COM port disappears

IoT Modules Legacy HL Series
1

Hi,

I’m using the eval board with HL7588 and Windows 10 connected through USB. When the USB composition is set up with kusbcomp=2, the MBIM adapter and COM port shows up in device manager but then after a few seconds the COM port disappears. Subsequent unplugging/plugging of the USB cable only makes the MBIM adapter disappear/reappear … the COM port never comes back. This can be reproduced on multiple host machines.

If i connect using RS232 i’m able to switch the USB composition to either option 0 or 1 and the COM ports show up properly. Sending a factory reset command or power cycling the board has no effect. Only with option 2 does the COM port not show up.

Grabbed latest firmware version: RHL75xx.A.2.10.151600.201604151852.x7160_1 and have the same behavior.

Any idea what may be going on here?

Thanks

2

hi,
It’s working fine at my end with older FW version… Will see with new one… Meantime make sure you have proper drivers installed.

-Alex