MosChip MCS7840 User manual

MCS7840/7820 User Manual for Windows Vista/Win7
Rev 1.0 Page 1 7/14/2011
MCS7840/7820
USB2.0 to Four/Two High Speed Serial Ports
User Manual
For Windows Vista/Win7 32-bit and Vista/Win7 64-bit
Contents: Page
1. Driver installation for Windows Vista/Win7 32-bit:.................................................. 1
2. MCS7840/7820 Device Installation & Detection:...................................................... 3
3. Uninstalling MCS7840/7820 Device & Drivers:........................................................ 4
4. Driver Installation in Windows Vista/Win7 64-bit:.................................................... 8
4.1 Preparing Vista/Win7 64-bit for Driver installation:.......................................... 8
4.2 Installing the Driver in Windows Vista/Win7 64-bit:......................................... 8
5. Support:....................................................................................................................... 9
6. Revision History:........................................................................................................ 9
1. Driver installation for Windows Vista/Win7 32-bit:
Download the MCS7840/7820 driver from MosChip Website at:
http://www.moschip.com/html/download_drivers.html. The driver disk consists of
MSSetup.exe, MSUninst.exe and related folders containing installation files.
Note: Do not get confused with the folder name in the Driver disk for Vista/Win7. It
could be anything, but makes no difference.

MCS7840/7820 User Manual for Windows Vista/Win7
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Use ―MSSetup.exe‖ utility to install the driver. Double click on MSSetup.exe to start the
installation process. Make sure that the User installing the driver must be a member of the
Administrator group on the system
You will get a ―User Account Control‖ window saying “An unidentified program wants
access to your computer”. Click on Allow to continue installing the Driver.
You will get an installation window as below, press ―Install‖ button to install the drivers
for High-Speed USB Multi Serial Device.
During the installation process, a ―Windows Security‖ warning message pops up
informing that "Windows cannot verify the publisher of this driver software". Ignore the
warning message by clicking on the option “install this driver software anyway”.
You will get the above message two times and you have to select “install this driver
software anyway”.

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The utility displays a message stating ―Installation completed‖. Use ―Exit‖ button to
complete the driver installation.
2. MCS7840/7820 Device Installation & Detection:
Connect MCS7840/7820 to the USB Host controller of the PC using a USB cable. The
first time you plug-in the cable into the USB port, Windows will start installing the
device driver software. You can see the installation status at the pop-up message of
system tray. After installation, the pop-up message says “Your devices are ready to use”,
Device driver software installed successfully.
MCS7840/7820 device detection can be confirmed by checking at the Device manager.
Check for ―MosChip High-Speed USB MultiSerial Compound Device‖under Universal
Serial Bus controllers and you will find ―MosChip High-Speed USB Serial Port (ComX)‖
under the category Ports (COM & LPT). Here ‗X‘ in ‗ComX‘ represents the serial port
number. You can see the same in the figure below.

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Note: In case of MCS7820, user can see only two High-Speed USB based serial ports
Now the MCS7840/7820 device is ready to use. You can connect a Serial Mouse or a
Modem and see if the serial port of MCS7840 works.
3. Uninstalling MCS7840/7820 Device & Drivers:
There are 3 methods to uninstall the driver for MCS7840/7820.
Method 1:
Use ―MSUninst.exe‖ to uninstall the MCS7840/7820 device driver from your PC. Double
click on MSUninst.exe to run the uninstaller. You will get a ―User Account Control‖
window saying “An unidentified program wants access to your computer”. Click on
Allow to continue uninstalling the driver.
When Uninstaller prompts for confirmation click on OK

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After uninstalling the driver, you will get the following window, where you need to use
the exit button to complete the uninstall process.
No need to restart the PC, unless prompted by the OS.
Method 2:
The driver can also be uninstalled through Control Panel –> Programs and Features ->
Select ―MosChip High-Speed USB MultiSerial Compound Device‖ from list and then
click Uninstall. This will remove the MCS7840 device driver from your PC

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Method 3:
The MCS7840 device driver can also be uninstalled through ―Device Manager‖ as well.
Go to Device Manager, Select MosChip High-Speed USB MultiSerial Compound Device
from the ―Universal serial Bus controllers‖, Right Click on it, Select ―Uninstall‖ as
shown below

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When prompted to confirm device uninstall, check the option ―Delete the driver software
for this device‖ and click on OK.
If you want to uninstall only the device, but retain the software driver for this device, just
click on OK without selecting the option ―Delete the driver software for this device‖.

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4. Driver Installation in Windows Vista/Win7 64-bit:
The 64-bit version of Windows Vista/Win7 is the first version of Windows that will only
allow signed drivers and this restriction is built-in. Currently, MCS7840/7820 drivers are
unsigned. Till we get signed drivers, we request you to follow some prerequisites before
installing the driver.
4.1 Preparing Vista/Win7 64-bit for Driver installation:
Using the F8 option: Press F8 key on your keyboard while booting your PC. You
will get into ―Advanced Boot Options‖. Select ―Disable Driver Signature
Enforcement‖.
An F8 Advanced Boot Option introduced with Windows Vista/Win7—―Disable
Driver Signature Enforcement‖—is available to disable the kernel-signing
enforcement only for the current boot session. This setting does not persist across
boot sessions. Note: Make sure to use F8 option every time you boot/reboot your
PC before start working with MCS7840/7820
Make sure that the User installing the driver must be a member of the
Administrator group on the system.
4.2 Installing the Driver in Windows Vista/Win7 64-bit:
Before running the installer (MSSetup.exe) or uninstaller (MSUninst.exe) utility of
MCS7840/7820, right click on them and select ―Run as administrator‖. The same is
shown in the following figure.

MCS7840/7820 User Manual for Windows Vista/Win7
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Note: Running the setup utilities as administrator is required, as “User Account Control
(UAC) is enabled by default in Windows Vista/Win7, which does not allow the user to
make changes to OS components. If UAC is disabled, you can install the driver without
running the setup utilities as an administrator.
The UAC can be turned ON/OFF at Control Panel -> User Accounts -> Click on ―Turn
User Account Control on or off‖ -> Here you can disable/enable the UAC.
The remaining install/uninstall procedure of Vista/Win7 64-bit is same as Windows
Vista/Win7 32-bit, as explained above.
5. Support:
Queries, Technical questions if any can be sent to [email protected] or
[email protected].
6. Revision History:
Version
Change Details
Date
1.0
Initial Release
22nd Dec, 2006