6 ISP Programming Does Not Work

  1. Do you have a proper connection?

    Ensure that the typical ISP 6 pin header is used and that it is not plugged in the wrong orientation. A read of the voltage with the programming tool can help to identify an improper connection.

  2. Do you use a Microchip programming tool?
    • If not, please describe the programming procedure with exact timing and data of all signals.

    If the error cannot be solved, trying a Microchip tool is recommended. If the error is still present, contact the technical support team.

  3. Do you keep the device awake?
    • Which pin is used to keep the device awake?

    As the NRSET line is used for ISP, the device might get a reset. If no wake source is present, the device enters the Off state. In this state, no internal clock is running and no further communication via ISP is possible. Therefore, it must be ensured that a wake-up source is permanently active during the complete programming/verify process.

  4. Did you set the correct ISP clock frequency; what frequency is used?

    Depending on the Sleep mode, it might be possible that only the SRC with typical 125 kHz is running. In this case, it is recommended that a clock not faster than 40 kHz be selected.

  5. Did you chose the right product? Which one?

    As the device ID will be checked during programming, an error will pop up if the wrong product is selected. Typically, the user will be informed of the correct product to select.

  6. Did you set the Lock bits?

    If the Lock bits are set, any further programming and/or read of the device is disabled. There is no other way to restore the Lock bit setting than with a chip erase. The chip erase will delete all data and software stored on the device.

  7. Did you set the DWEN fuse?

    Once the DWEN fuse is set, no further ISP access is possible. A debug session must be started to be able to clear the DWEN fuse.

    If the issue could not be solved with the troubleshooting descriptions in this document, contact the technical support team for further guidance and assistance with your issue.