Use QSI Quantum Programmer
JMRI Decoder Pro - NB: Windows Only


Download PDF version of these Instructions

Download SiLabs VCP Drivers ver 5.3

Download Modified
slabvcp.inf file ver 5.3

Download Latest versions of QSI Programs

Installing SiLabs VCP Drivers for QSI Programmer
 for the JMRI Decoder Pro Version 2.2 using Windows

The SiLabs Virtual Com Port Drivers (VCP) can be used with the QSI Programmer so that the JMRI Decoder Pro will recognize the Com Port the Programmer is on.  To accomplish this, the best method is to remove the SiLabs USBXpress Drivers required by the QSI Solutions Programs and REPLACE them with the SiLabs VCP Drivers entirely!  Warning!  Make sure you have the latest versions of  
Q1A and Q2 Upgrade Programs and the Quantum CV Manager Programs so you can use these with the VCP Drivers.  These Programs will NOW work with both the SiLabs USBXpress USB drivers and the SiLabs VCP drivers  This means that you can replace the USB Drivers and now using one set of drivers for BOTH QSI Program AND JMRI Programs.  Use following steps to uninstall USBXpress Drivers, Reconfigure the VCP Drivers Setup File, Install and Configure the VCP Drivers and Setup JMRI Decoder Pro and the QSI Programs for use with the QSI Programmer.


1.)  Remove USBXpress Drivers for QSI Programmer. Using the Add / Remove Programs from Control Panel, remove any   SiLabs USB drivers or USBXpress Drivers installed for the QSI Programmer. If no drivers are present in the Control Panel, but the QSI Programmer is still working, then Uninstall QSI Programmer from Device Manager.  To Open the Device Manager, right click on My Computer, choose Properties. Choose the Hardware Tab. Then Click the Device Manager Button. (Also available from the Control Panel, System Icon.)With the QSI Programmer powered and connected with the USB cable, right click and choose uninstall.  Then unplug the QSI Programmer USB cable.

Figure 1 - Add/Remove Programs

Figure 2 - Device Manager

Figure 3 - Quantum Programmer after right click

Figure 4 - Confirm Removal of Quantum Programmer

Figure 5 - Device Manager with Programmer Removed

2.)   Download and Unzip from  
From the CP210x_VCP_Win2K_XP_S2K3 folder run CP210x_VCP_Win2K_XP_S2K3.exe  using the default settings. Open the SiLabs folder created by the install.  Expand the MCU folder, and then expand the CP210X folder.  Click on the folder named Windows_2K_XP_S2K3_Vista.  In this folder is a file named slabvcp.inf. 

Figure 6 - Location of slabvcp.inf

Open this file with notepad.  This can be done by right clicking on the file and choosing Open.
Using edit / find from the menu, you can type in the Find What box:  PID
You will find 5 entries with the following:  PID_EA60
Change EA60 to 8208 on all five entries.  All 5 instances should now look like this: PID_8208
Be careful not to change or remove any other entries that PID is part of.

Click file, save on the open notepad.  Close notepad.     
This change will allow the VCP drivers to see the SiLabs Chip inside of the Programmer.
(A copy of this file can be downloaded from the link above.. If you use this file, replace the original slabvcp.inf with this version)

Figure 7 - Modification of slabvcp.inf

3.)  Execute CP210xVCPInstaller.exe from the same folder that slabvcp.inf is in. Use the default settings   and click install from the CP210X USB to UART Bridge Driver install Window.  Choose 'Continue Anyway' button, IF you get the Windows Driver Warning "...has not passed the Hardware Compatibility Logo   Testing".

Figure 8 - CP210X Installer

Figure 9 - Windows Logo Warning

4.)     The Virtual Com Port will NOT show up in the device manager until you plug in the QSI Programmer   and configure it to use the SiLabs VCP Drivers.

Figure 10 - Device Manager with Quantum Programmer Removed

 With the Power Cable connected and powering the QSI Programmer, plug it in to the USB port of your  computer.

 The "Found New Hardware Window" should open, if you have successfully removed all of the USBXpress Drivers.

 Choose "NO" to search Update Site for Drivers.  Then Click Next.                                                       

Figure 11 - New Hardware Found

Choose the default "Install Software Automatically" (recommended) setting and click Next. Choose Continue Anyway Button if you get the Windows Driver Warning "...has not passed the Hardware Compatibility Logo Testing". Drivers will finish installing.  Choose Finish when drivers are installed.  You might get an information "balloon" from the notification area, by the clock that the Hardware is installed and ready to use.

Figure 12 - Hardware Wizard set to Automatically Install

Figure 13 - Windows Logo Warning

5.)  Open Device Manager and confirm that the SiLabs Virtual Com Port is installed in the ports section. The driver will assume the first available Com Port. (Normally 2 or 3)  (On this test machine it found Port 8 as the first Available.) What Ever port is found should show up in the Preferences Window of the JMRI Decoder Pro.

Figure 14 - SiLabs Virtual Com Port (note port number)

(You can change the port by using the Advanced Button on the Ports Tab available from the properties window of the VCP. Make sure not to choose a Com Port already in use.)

Figure 15 - Right Click Menu on the Virtual Port

Figure 16 - Virtual Com Port Options for Port Settings

Figure 17 - Advanced Settings for Virtual Port

Figure 18 - Com Port Settings

6.)  Using the preferences option of JMRI Decoder Pro, choose QSI Programmer and the Com Port that the VCP is using.

Figure 19 - Decoder Pro Preferences with QSI chosen

Figure 20 - Reading Loco Address from QSI version 7 Chip

Figure 21 - Idle before Read to Locate Loco in Roster

Figure 22 - Reading Loco and searching Roster

Figure 23 - Loco found in Roster and Identified

Figure 24 - Choose Menu from Icon at top left corner

Figure 25 - After clicking Quantum Programmer, choose option button
and configure choice of VCP Driver and Port Number


Figure 26 - Choose Command Station, Command Station Options then
Choose Quantum Programmer Options


Figure 27 - Configure Choice of  Virtual Driver and Port Number

      By using these Instructions and steps, YOU are accepting ALL responsibility for any damages and issues; use this project at your own risk as these instructions come with no warranty, express or implied.  These instructions are limited to adapting SiLabs VCP Drivers  for use with the QSI Programmer.  Suitability for use with JMRI Decoder Pro is neither Implied or guaranteed.  Nothing in this article is meant to imply that Decoder Pro will work properly with this SiLabs VCP Adaptation.  Contact JMRI for issues and questions regarding Decoder Pro.

My permission is given to include any or all of these steps and graphics for use on JMRI Decoder Pro Instructions  and/or Help Files and/or JMRI websites; for use on QSI/QSI Solutions instructions and/or Help Files and/or QSI/QSI websites.  Additionally, you may download this article for your personal use and research. You may also make copies and distribute them to other individuals providing that the article is copied in its entirety, including the email address and site link,  that no fee is charged, and this notice remains intact.  You may link to the web page this article is on or the Web Site, provided you do not incorporate it in a frame or other method that would lead the average user to believe that it is part of another Internet site. You may not 'mirror' this article or this site without permission of the owner

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(updated July 23, 2008)