How to Update the Firmware of a MAX32664 on a Custom PCB

First, we will need to flash a firmware image to the MAX32630FTHR microcontroller.   To do so, follow the steps below:

1. Connect the JTAG Cable from the MAX32625PICO to the MAX32630FTHR, and connect both devices to your PC with a micro-USB cable.
   
2. The DAPLINK drag-and-drop programming interface of the MAX32625PICO will appear in your list of devices and drives.
   
3. Drag and drop the “MAX32630FTHR_msbl_flasher.bin” file from the latest MAX32630FTHR_msbl_flasher software package onto the DAPLINK drive.  You will see the LED on the MAX32625PICO blinking as it programs the MAX32630FTHR.
   
4. Once complete, unplug both devices from your PC.  You can remove the JTAG cable and the smaller "PICO" programmer board, it's no longer needed.  Your MAX32630FTHR is now ready to be connected to your PCB to flash your MAX32664!

Your PCB will need to have the SLAVE_SCL, SLAVE_SDA, MFIO, and RSTN, and VSS (GND) pins of the MAX32664 exposed.  Refer to the MAX32664 Datasheet for pin #s for your package type.

1. Connect the following pins together.

2. Connect one of the GND pins of the MAX32630FTHR to the GND reference on your PCB that is connected to V_SS (Digital ground) of the MAX32664.  This is very important to ensure I2C and GPIOs work properly.
3. Provide the necessary 3.3V to V_DD on the MAX32664 to power on the IC.  This will depend on how your PCB is laid out.  The 3.3V supply can come from the 3.3V output on the MAX32630FTHR if necessary.  3.3V is used to match the logic level of the MAX32630FTHR firmware.  If your PCB uses a 1.8V supply, a logic level translator should be used for the I2C bus and GPIOs so as not to exceed that absolute max ratings of the MAX32664 pins.  It is recommended to use a 3.3V supply for the MAX32664 during the flash for the sake of simplicity.

Use the micro-USB connector to re-connect the MAX32630FTHR to your PC.  Take note of which COM port the MAX32630FTHR is using.  On Windows, it will show up as a generic USB Serial Device.

    

1. (Optional) Copy the .msbl file for your MAX32664 variant into the same directory as the “flash.exe” executable for your own convenience.  Otherwise, the -f option below will need to include the full file-path to the .msbl file.
2. Open a command prompt or shell in the same directory as the "flash.exe" executable.  Run the executable.  You can copy the following command as a template, or run "flash.exe -h" for help.
   
   flash.exe -f "[your msbl filename]" -p "[MAX32630FTHR COM port]"

If you are using Linux or Mac, the Python scripts inside of the "Python" directory of the software download can be used as an alternative.  From within the Python folder...

​​​​​​pip install -r requirements.txt
python flash.py -f "[your msbl filename]" -p "[MAX32630FTHR COM port]"

Alternatively, on Windows the included "run.bat" file can be used. This file will prompt the user to select from a list of .msbl files that were copied in the same location as the "flash.exe" file. Once the file has been selected by the assigned list number, then the console prompts the user to enter the assigned COM port to the MAX32630FTHR. Once this has been entered the program proceeds to flash the msbl file as shown below:

3. Monitor the command line output for any errors.  An example of a successful flash of a MAX32664 on a MAXREFDES220 PCB is shown below…

After a successful flash, the host script will attempt to reset the MAX32664 to application mode and read off the new firmware version #.  Check the last line of the flash to ensure that the retrieved version # matches.  For example...