TRU: Recovering Receiver Boards After Firmware Loading Failed

How to recover a receiver board using firmware loading via Power Capture Mode (TRU)

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TRU: Recovering Receiver Boards After Firmware Loading Failed

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  • User tried to upgrade GNSS board firmware
  • Firmware upgrade has been aborted because of power interuption or other external circumstances or wrong firmware has been loaded
  • Result: Receiver is unresponsive; does not respond to any action
  • Solution: Reloading correct firware with Power Capture Mode could recover the receiver board

Preparing Connection to Receiver:

  • It is mandatory to have a real serial connection to receiver,
  • It is not recommended to use USB-to-Serial convertor
  • Unplug external power supply and remove the battery from receiver, or let the internal battery drain completely (HiPer SR, HiPer Pro, etc.)
  • Connect the receiver with serial cable (14-008005-03) to PC
  • Start TRU (latest version) on PC and change the [Device] / [Application Mode] to [Firmware Loading] (F5)
  • Click [Device] and [Connect],
  • Set “Connect Using” to [Serial Port] and “Port Name” to the COM port number of your PC
  • Click [Connect]

Preparing Firmware Loading With Power Capture Mode:

  • The screen now turns active
  • Click on [Firmware Loading]
  • “Device Type” is [Receiver]
  • Change “Capture Method” to [Power On]
  • “Serial Port Settings” can basically stay as default. It could be necessary to try different baud rates if default 115200baud fails to connect
  • Click [Next]
  • The next window stays empty, because the real connection is not done yet, TRU cannot read receiver information.
  • Click [Next]
  • Browse here to current firmware version
  • “Loader” is requesting the ramimage.ldr
  • “Image” is requesting the main.ldp
  • Make sure you use the correct firmware for your receiver. If you are uncertain, please ask your dealer and mention detaild receiver type - at least the serial number
  • Click [Next] after choosing the correct files

Start Firmware Loading With Power Capture Mode:

  • TRU is now waiting for a power cycle of the receiver
  • Replace a fully charged battery to receiver if possible, or better, plug the external power supply to receiver.
  • In some cases it is necessary to push the power key for 1 second after plugging in the power cord

Firmware Loading:

  • If receiver is not turning on automatically, push the power key for 1 second
  • TRU is now starting to flash firmware on receiver board
  • After firmware is loaded, receiver restarts automatically