Bosch Sensortec Community

    Showing results for 
    Search instead for 
    Did you mean: 

    BMF055- Program halts on custom design

    BMF055- Program halts on custom design


    Hello everyone,

    We had purchased the BMF055 shuttle board along with breakout board and tested it out. Once satisfied, we had tried to implement the same into our customized board which replicated the circuit details as mentioned in the BMF055 shuttle board.  But, after programming the BMF055 IC and starting the debugging process, the program gets stuck in the "gclk.c" file at while loop (Highlighted line in attachment). We have rechecked the schematic connections of our board with the BMF055 Shuttle board and there are no changes to be found. We are using Atmel Studio IDE and Atmel ICE debugger for our debugging of the BMF055 IC. The example program used by us is "BMF055_DATA_STREAM-atsamd20j18".

    Please support us in resolving this issue.

    Thanks & regards,

    Rajeev K Nair

    9 REPLIES 9

    Community Moderator
    Community Moderator


    It seems like an issue with the crystal or GCLK initialization. Are you using the crystal?

    The examples may not have been updated with the latest Board Support Package drivers from Atmel and hence may not have the latest work-arounds in the underlying drivers. Shortcut to the SAMD20J18 Errata sheet.



     Thank you for your reply. 


    Will share by private message.


    We are not using the crystal. Its the same way as in the default code available for download in Data stream example. Also, the BMF055 is working without issues in the shuttle board. 


    Hi FAE_CA1,

    Please support us in solving the issue with the BMF055 IC.

    Also, is it possible to share the BMF055 shuttle board layout with us? It would help us to compare with our custom PCB and resolve any errors that might have been created while designing our PCB. 

    Thanks & regards,



    Community Moderator
    Community Moderator

    In your previous comments,  you said you are not using external crystal  but i found 32KHz crystal on your schematic.  

    Does it mean you just not install it on PCB?

    If it is the case,  you can take a look the errata which my colleague shared to you in comments.  there is some extra things need to be take care in your code.  

    I also attached the BMF055 shuttle schematic in the attachment.  

    Community Moderator
    Community Moderator

    Could you also try to add GND on C1 and C5?