All of the latest versions of essential firmware configuration programs, USB driver and their associated documentation can be obtained from Fred PE0FKO's website:

In order to test (and later, operate) your rig, you must download and install required software (SDR programs and Dynamic Link Libraries, along with hardware drivers. The actual steps and programs may vary, depending upon your computer's windows operating system version (XP, Vista, Windows 7, 8, or 10) and architecture CPU/memory (32 bit or 64 bit). Generally, the process involves the following:

  1. Install the libraries and drivers (PE0FKO'a "All-In_One" Installer
  2. Test installation using CFGSR
  3. When ready to operate, install desired SDR program (e.g., HDSDR, SDR#, Rocky, PowerSDR, etc)

The following links are provided and, as of 1/22/2012, are current. Links highlighted in an Aqua-colored background apply only to those Softrock kits that use the SI570 programmable oscillator:

Software Role/Purpose Function Download Link Notes
CFGSR Configure/Control Ensemble microcontroller Configure download See the FiveDash documentation for software installation
SRDLL dll for other Softrock controllers Control (now part of CFGSR install file, so no need to go out and find/install it separately.)
New All-In-One Driver Installer
(See Section Titled "Install the PC driver software automatic"
New installer for "signed" PE0FKO-USB-Driver from Fred, PE0FKO. Driver Download See the FiveDash documentation for software installation
USB driver(s) drivers for ATTiny85 USB Driver download Zip file with 32 and 64 bit drivers (latest version is*.
Preferred installation method is the "All in One" method depicted above and further described in the FiveDash documentation for software installation .
(32/64 bit Windows 7, Vista, XP) PowerSDR-V2.4 For Homemade SDR Transceivers Latest Version of FlexRadio's PowerSDR tailored for I/Q Soundcard-based SDRs. Click here for installation instructions. RXTX download Has Si570 Control Capability ( Please see Christos Nikolaou' message 2583 on the PowerSDR-IQ Yahoo Reflector). This is good for all Windows platforms and handles RX and TX in all modes. All required software (to include the All-In-One USB Driver Installer) is furnished. One needs only to download the basic FLex PowerSDR V2.4.4 from the Flex site) to have a complete software solution.
This is the most comprehensive of all the packages. However, commensurate with its power comes a steep learning curve.
SDR # SDR # ("SDR Sharp") for RX RX Download Very good and simple program (RX only; TX tbd) from Youssef Touil. Alan, G4ZFQ, has a nice article on setting up SDR# for an Ensemble RX II.
Rocky (V3.7). (V3.8 has been developed for later Windows versions) Simple SDR (RX/TX) Program (see note below) RXTX download SSB RX, CW and PSK-31 RXTX. Great little Windows-based program (but it has hsd its issues with more modern versions of Windows - soundcards. The later version of Rocky - V3.8 - addresses many of these issues.).
HDSDR (V2.7) Elegant SDR (RXTX) Program (based upon original Winrad) RXTX download CW is very basic and only properly useable on the older 6.3 Softrocks. For installation and setup info, see: these pages from Alan, G4FZQ. Also, see the FiveDash documentation for software installation
(Windows XP) PowerSDR-IQ V1.12.20 Version of FlexRadio's PowerSDR tailored for I/Q Soundcard-based SDRs RXTX download Has Si570 Control Capability.
Based upon recent experience, the PowerSdr v2.4 above is recommended in lieu of this version.
(Windows 7, Vista) PowerSDR-IQ V1.19.3.15 Earlier version of FlexRadio's PowerSDR tailored for I/Q Soundcard-based SDRs RXTX download Based upon recent experience, the PowerSdr v2.4.4 above is recommended in lieu of this version.
Has Si570 Control Capability (Please see Christos' message 43204 on the Yahoo Reflector)
com0com An open source null modem/virtual serial port manager Utility (VSP) Com0com is useful for interfacing third-party CAT-based software (e.g., HRD, FLDIGI, etc.) with PowerSDR or other CAT-capable SDR programs. Christos Nikolaou, SV1EIA, has provided this signed version of com0com's installation file for Windows 7 64 bit OS (which requires a signed version).
VAC Virtual Audio Cable - a software audio "patch cable" Utility (VAC) - Free trial (but don't use trial on the air!) Website for download: VAC is indispensible when attempting to interface thrird party programs (e.g., HRD, FLDIGI, etc.) with SDR Programs. It allows us to "patch" audio to and from the soundcard to another program.
*Note on installing PE0-FKO's USB Drivers: Fred's website has an excellent step-by-step guide to instaling the USB driver. However, see the All-In-One installer (it renders the instructions unnecessary)

Install Driver

To be extra safe, it is highly recommended that you install the drivers with no other USB devices connected directly to your PC during the install. If your mouse and/or keyboard are USB, reconnect them through a USB hub. This seems to help avoid the dreaded "Unknown Device" Problem.

If you do not use the All_in_One Installer from PE0FKO, the correct procedure is to download the driver and put it in a suitable folder, then plug in the USB lead, Windows should detect new hardware has been found and you need to manually point it to the folder containing the drive. It should then install correctly. Certainly does on Win2000 and XP. On Vista or Windows 7, there used to be some issues with driver signing. There have been messages on the forum describing methods of working around these issues. One such solution is addressed in the author's MOBO4.3 builders notes.

LibUSB - "Unknown Device" Error

Others have experienced the dreaded "Unknown Device" problem upon plugging in the USB cable after having installed the LibUsb driver. This "unknown device" problem (and a remedy for those who are using Logitech cordless mouse and/or various wireless internet connection adaptors) are discussed in message #45071 and Message #47755 on the Yahoo Softrock40 Group

Another valueable resource for troubleshooting the "unknown device" error is Alan's webpage Installing the ATTiny45/85_USB Controller

Install/Run CFGSR ("ConFiGureSoftRock") (automatically installed in All-In_One Installer)

Once the driver is installed, if you run 'CFGSR' that will either automatically 'open' the firmware, or if not, you need to go to the 'USB' tab and select it from the list displayed in the bottom box. Which way depends on if you have 'CFGSR' set up to auto connect on program start or not.

Following configuration with CFGSR, it is adviseable to use one of the simpler SDR programs for initial testing of RX (and/or TX) functionality, even though you may want to have a more robust piece of software as your ultimate radio.

For further discussions of the software side of SDR and soundcard issues, see Alan G4ZFQ's pages.

Test Local Oscillator Using CFGSDRr

You can use 'CFGSR' to exercise the Si570 using the 'Tune' tab that makes it into a 'VFO'. Just a case of setting the frequency, and the Si570 should output a signal at 4 times the frequency displayed on the main display on the screen. Tuning can be done either by typing in the frequency or by using the mouse wheel to change the frequency by increments ranging from 1kHz to 10 MHz.

The 'Test' tab can also be used to look at all the various Si570 registers etc, but probably unnecessary as if you can hear or measure the Si570 output frequency, you know it is working.

Optionally, Install SD Program

You may, if you wish, install the SDR program of your choice here (e.g., HDSDR, Rocky, SDR#, etc.). However it is not necessary until the final stage of the build project, when you test out the receiver.

usbsoftrock" [Linux]:There is also a usb driver for Linux platforms. it's no longer available from the Google Code repository, but is still available in various Linux distros and in Alex Lee's github repo at