USBDM  V4.12
Installation & Initial Programming of BDM Firmware

Initial Construction and Installation.

  • This version of USBDM may be used with several existing types of hardware including the original TBDML circuit. You can compare your hardware with the circuit diagrams provided in the firmware directory to aid in identification.
    Alternatively, a new (simplified) design is provided.
  • Build the hardware using the information provided in the PCB folder.
  • The following are provided:
    • PDFs including the circuit diagrams with parts lists and example PCB layouts.
    • PCB layouts in Altium designer format (a trial version of the software may be down loaded from http://altium.com/evaluate/).
    • PCB layouts exported from Altium designer as Gerber files and NC drill files.

Programming of USBDM into a JB16 device

Refer to the following document for detailed information on how the JB16 operates in in-circuit-programming (ICP) mode (or search for AN2399 on the Freescale web site):
AN2399 : In-Circuit Programming of FLASH Memory via the Universal Serial Bus for the MC68HC908JB16

Discussion

  • Make a backup of your TBDML/OSBDM code if modifying existing hardware.
    Make sure you have a copy of your current TBDML/OSBDM code so you can restore it if my code doesn't work with your hardware.
  • Obtain the USBDM code for the JB16 flash memory.
    Choose a pre-compiled image from the Flash_Images directory. Refer to the documentation provided in the folder for details of the software and how to identify the appropriate flash image file to use.
  • Download of code to JB16 flash using bootloader
    The JB16 chip contain a small USB boot-loader in ROM that is used to update the firmware stored in the Flash. Unfortunately this boot-loader is incompatible with later versions of Windows (Windows-XP SP3 and later). Due to this it is unlikely that it would be possible to update the firmware on a Windows machine. The following process assumes a Linux machine but may work on a very early Windows OS.
  • A blank JB16 will normally boot in ICP mode with the boot-loader active - Refer to AN2399 above.
    • Alternatively, it will be necessary to use whatever method your original TBDML hardware/software used to get into ICP mode. For most hardware this process required holding port pin A.0 low while plugging in the BDM. This also applies to USBDM but it has an alternative software method.
    • If the device already has an existing USBDM firmware present then the software method may be used to get into ICP mode (see following steps)
    • A utility JB16 Bootloader is provided to do the actual download to the target - This has only been tested on Linux.

Programming Steps.

  • Do one of the following:
    • Hardware triggered ICP - Connect pin A.0 to ground and plug in the BDM. The hardware will boot in ICP mode.
      OR
    • Software triggered ICP (existing USBDM only) - Just plug in the BDM hardware.
  • Start the JB16 Bootloader program.
  • If updating a BDM with existing USBDM firmware then press the Reboot button.
  • Select the appropriate firmware to load.
  • Press the Program button and wait.
  • Remove and replace the BDM.