
Rev. 1.0
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CP2103
8. CP2103 Device Drivers
8.1. Virtual COM Port Drivers
The CP2103 Virtual COM Port (VCP) device drivers allow a CP2103-based device to appear to the PC's
application software as a COM port. Application software running on the PC accesses the CP2103-based device
as it would access a standard hardware COM port. However, actual data transfer between the PC and the CP2103
device is performed over the USB interface. Therefore, existing COM port applications may be used to transfer
data via the USB to the CP2103-based device without modifying the application. See “AN197: Serial
Communications Guide for the CP210x” for example code for interfacing to a CP2103 using the Virtual COM
drivers.
8.2. USBXpress Drivers
The Silicon Laboratories USBXpress drivers provide an alternate solution for interfacing with CP2103 devices. No
serial port protocol expertise is required. Instead, a simple, high-level application program interface (API) is used to
provide simpler CP201x connectivity and functionality. The USBXpress for CP210x Development Kit includes
Windows device drivers, Windows device driver installers and uninstallers, and a host interface function library
(host API) provided in the form of a Windows Dynamic Link Library (DLL). The USBXpress driver set is
recommended for new products that also include new PC software. The USBXpress interface is described in
“AN169: USBXpress Programmer's Guide.”
8.3. Driver Customization
In addition to customizing the device as described in
“7. Internal EEPROM” , the drivers and the drivers installation
package can be also be customized. See “AN220: USB Driver Customization” for more information on generating
customized VCP and USBXpress drivers.
8.4. Driver Certification
The default drivers that are shipped with the CP2103 are Microsoft WHQL (Windows Hardware Quality Labs)
certified. The certification means that the drivers have been tested by Microsoft, and their latest operating systems
(XP and Vista) allow the drivers to be installed without any warnings or errors.
The customized drivers generated using the AN220 software are not automatically certified. They must go first
through the Microsoft Driver Reseller Submission process. Contact Silicon Laboratories support for assistance with
this process.
Table 10. Default USB Configuration Data
Name
Value
Vendor ID
10C4h
Product ID
EA60h
Power Descriptor (Attributes)
80h
Power Descriptor (Max. Power)
32h
Release Number
0100h
Serial Number
0001 (63 characters maximum)
Product Description String
“CP2103 USB to UART Bridge Controller” (126 characters maximum)