EPP-4 FAQ: Frequently Asked Questions

The information on this page is meant to help you troubleshoot encountered problems. Please try if the items below do solve your problem. Always make sure you have the latest software version installed on your PC. The latest software can be downloaded from this website in the EPP-4 software section.

Q: 1. I always get error messages when the PC program starts
2. Any action (read, check, write, etc.) to the programmer fails
A: The PC software can only be used when the EPP-4 USB interface has completely been detected and installed by the operating system. Therefor the start up sequence is as follows:
  • Connect the USB cable to the PC and the EPP-4.
  • Connect the power supply to the EPP-4.
  • Turn on the EPP-4.
  • Wait until the USB detection is complete. This can take up to 15 seconds and differs per operating system and PC speed.
  • Start the PC application.
  • Q: I keep getting the message "Error 49 USB <any action> Command Fail"
    A: It is not needed to turn off the power of the programmer to change a component in the ZIF socket. When the Busy LED is OFF, and the PC software is not communicating with the programmer, any IC in the ZIF socket can safely be removed or replaced.

    Q: When reading the IC in PC mode, it is always blank or the content is totaly wrong
    A: When using the EPP-4 in PC mode, only the SLAVE socket should be used. The MASTER socket should be empty.

    The MASTER socket is only used whenever the EPP-4 is used in stand-alone mode (without PC). In this case the source IC should be placed in the MASTER socket and the target IC in the SLAVE socket.

    Q: I want to program a 27Cxxx or 28Cxxx device but I can't find it in the device list
    A: Select 27XXX (for 27Cxxx devices) or 28XXX (for 28Cxxx devices) as brand in the device selection menu. After this select the device which matches the size of your component.

    Q: What is the basic operation of the EPP-4 PC software?
    A: Basically operation is reasonably simple. If you look well you will notice a line with arrows in the "Source" part of the screen. In this screen you have to perform your first series of actions:
  • Select device [Type]
  • Get the source file:
  • A: Read from disk [Load]
    B: Read back from an IC [Read]
    Confirm will read the device again and check it with the previous read version. De-selecting the check box will disable the confirmation read and speed up the process.
  • Now you can edit the memory if needed [Edit] and if needed save the file to disk for later use [Save]


  • The lower part of the screen has controls the several programming process and options which may vary depending per device type:
  • Erase:
  • Click the icon to only erase the component
  • Check:
  • Click the icon to only check if the component is empty
  • Prog:
  • Click the icon to only program the device
  • Verify:
  • Click the icon to only verify is the correct contents is in the device
  • Prot:
  • Click the icon to only (write) protect the component

    You can also perform a sequence of actions by clicking the Play [>] icon. All programming actions of which the select box have been enabled will be performed.

    Q: The above items do not solve my problem, what should I do now?
    A: If the above does not solve your problem, please send an e-mail to Anti spambot security meassure! containing the following information:
  • The type of product
  • The serial number
  • The operating system you use
  • A detailed description:
  • What are you trying to do?
  • What device are you trying to program (brand and type number)?
  • What device have you selected (brand and type number)?
  • Which operation mode do you use (PC operated or Stand Alone)?
  • What steps do succeed and what don't?
  • What messages do you get?

  • Please add any information, screen dump or other data that you have available and may give us detailed information regarding your request.