Skip to main content
arro239
arro239
Associate III
December 30, 2014
Question

how to hold stm32f4discovery in place?

  • December 30, 2014
  • 9 replies
  • 1617 views
Posted on December 30, 2013 at 19:42

Is  it safe to drill the f4discovery board? For example around the SWD connector or the ST logo?

I need to connect the discovery with a 10x10 expansion board I am designing. I am probably planning to have my board under the discovery so that I still have access to the LEDs and the reset button. I know that there is an option to solder my board to discovery, but that would be the last resort. So, I want to hold the boards together with more than just the pin header, so I am thinking about bolting them together, so I need a safe spot to drill the discovery board :)
    This topic has been closed for replies.

    9 replies

    ilmars
    ilmars
    Visitor II
    December 30, 2014
    Posted on December 30, 2013 at 20:19

    Don't even think of drilling. If you even manage to find safe spot around logo what you will do with other end of the board? Anyway you shall study

    http://www.st.com/st-web-ui/static/active/en/resource/technical/layouts_and_diagrams/board_manufacturing_specification/stm32f4discovery_gerber.zip

    then. F4discovery have so much pins - why you need to hold it using screws?
    arro239
    arro239Author
    Associate III
    December 30, 2014
    Posted on December 30, 2013 at 21:03

    Thank you for the gerber files!

    I want to use the board in a car so there will be vibration. I guess even one single bolt in addition to the pin headers would help a bit?

    ilmars
    ilmars
    Visitor II
    December 30, 2014
    Posted on December 30, 2013 at 21:18

    I guess even one single bolt would help a bit?

     

    Single screw at one corner can make things worse. So you need two screws at least. But corner around audio jack is very busy - no place for hole. Look at f4discovery board pin layout - there's four pairs of GND pins at corners. You can ''tie'' F4 board to mainboard using wire and soldering iron. No screws to come lose :)
    arro239
    arro239Author
    Associate III
    December 30, 2014
    Posted on December 30, 2013 at 21:33

    So the 5.05 mm outside of PB7 and lower are pretty much free? That's the bottom-right corner. I know it's kinda on the side, I can put two smaller bolts there

    And another one between the pins and SWD connector, to the left from C17&C18? Seems like like an open space too?

    Technically I do not need the audio jack so if I remove the jack the would be a spot between the jack and the pins.

    ilmars
    ilmars
    Visitor II
    December 30, 2014
    Posted on December 30, 2013 at 21:59

    If you want to use your drill - do it. I give up :) Just don't use metallic screws.

    raptorhal2
    raptorhal2
    Lead
    December 30, 2014
    Posted on December 30, 2013 at 22:07

    If you have the room, a simple answer is to use a hardware store electrician's plastic tie wrap around both assemblies.

    You didn't identify the type of car, so we can only guess at a suitable answer. A street car or or even a hot rod style won't vibrate the assemblies apart using just the headers. A car with tire shake at launch can shake any screw loose.

    Have you allowed for vibration effects on the User and Reset push buttons and on the jumper blocks ?

    Cheers, Hal

    arro239
    arro239Author
    Associate III
    December 30, 2014
    Posted on December 30, 2013 at 22:23

    Endurance road racing car.

    Great point about the reset button and the jumpers, I guess the simple answer is I should overcome my laziness and make a custom board :)
    Andrew Neil
    Andrew Neil
    Super User
    December 31, 2014
    Posted on December 31, 2013 at 01:03

    Look for something that will grip the board by the edges?

    Or a board that provides proper mounting points.
    A complex system that works is invariably found to have evolved from a simple system that worked.A complex system designed from scratch never works and cannot be patched up to make it work.
    raptorhal2
    raptorhal2
    Lead
    December 31, 2014
    Posted on December 31, 2013 at 01:54

    I have built a few ProMod data loggers and have some sensors, connectors, enclosures and experience left over. Contact me at raptorhal@bellsouth.net if interested.

    Cheers, Hal

    Terms & ConditionsAccessibility statement