9710:7840 — MCS7820/MCS7840 2/4 port serial adapter
MosChip Semiconductor
- Vendor ID
- 9710
- Product ID
- 7840
- Combined
- 9710:7840
- Decimal
- 38672:30784
What is this device?
This is the USB identifier for a MCS7820/MCS7840 2/4 port serial adapter manufactured by MosChip Semiconductor. The vendor ID 9710 is registered to MosChip Semiconductor with the USB Implementers Forum, and 7840 is the product ID that MosChip Semiconductor assigned to this particular model. When you run lsusb on Linux, this device appears as 9710:7840 MosChip Semiconductor MCS7820/MCS7840 2/4 port serial adapter.
How to identify it on your system
Linux
$ lsusb Bus 001 Device 004: ID 9710:7840 MosChip Semiconductor MCS7820/MCS7840 2/4 port serial adapter
You can filter directly with lsusb -d 9710:7840, or get the full descriptor dump with lsusb -v -d 9710:7840. Kernel messages from dmesg show the same pair as idVendor=9710, idProduct=7840.
Windows
In Device Manager, open the device, go to Details → Hardware Ids. This device reports:
USB\VID_9710&PID_7840 USB\VID_9710&PID_7840&REV_0100
From PowerShell: Get-PnpDevice | Where-Object InstanceId -match "VID_9710&PID_7840"
macOS
$ system_profiler SPUSBDataType
MCS7820/MCS7840 2/4 port serial adapter:
Product ID: 0x7840
Vendor ID: 0x9710 (MosChip Semiconductor)Driver help
Having driver issues with this device? Most USB devices are handled by a generic class driver; if yours shows up as an unknown device, confirm the ID above first, then check the manufacturer's downloads page.
Raw usb.ids entry
The exact lines this page is generated from, in the upstream source file:
9710 MosChip Semiconductor 7840 MCS7820/MCS7840 2/4 port serial adapter