Setting the Win7 1394 Bus Driver to the Legacy Version

For the Firewire-based FLEX-5000 and FLEX-3000 connected to Win7 PCs, you may experience intermittent connection behavior due to software defects in the native Win7 1394 bus driver that interfaces with your Firewire card.

The following instructions describe how to revert to the legacy 1394 Host controller bus driver. This driver is provided for backward compatibility for Firewire card drivers that are not fully compliant with the new Windows 7 1394ohci.sys driver architecture.

Step 1. Shut down PowerSDR and power off your SDR.

Step 2. Opening the Windows 7 Device Manager

Click on the Start button. Now, type devmgmt.msc in the box with the text "Search Programs and Files" and press the <Enter> key. This will open the Device Manager.


Step 3. Expand the IEEE 1394 Bus host controllers object so you can see the installed 1349 host controllers

Step 4. To do this, locate the Firewire (1394) controller in the Device Manager tree that you will be using with your FLEX-x000 software defined radio, right-click it, and select Update Driver Software.... This will open the Update Driver Software window.


Step 5. Now, select the Browse my computer for driver software (Locate and install driver software manually.) option. This will advance you to the next window where you will be prompted to browse for driver software on your computer.  Read ahead, because you will not be doing any browsing.


Step 6. Now, beneath the browsing option select Let me pick from a list of device drivers on my computer (This list will show installed driver software compatible with the device, and all driver software in the same category as the device.). This will advance you to the next window where you will be prompted to select the device driver you want to install for this hardware.


Step 7. Now, select the 1394 OHCI Compliant Host controller driver with the word Legacy appended to it and then click Next. This will advance you to the next window where the driver will be installed. 


Step 8. When the installation is complete you will advance to the final window where you are informed that Windows has successfully updated your driver software.

You may be prompted to reboot your computer.  If so, please reboot your computer before powering up the 

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