PIC24 IMU development

benoitstjean · Posted: Wed Dec 03, 2025 10:08 am

Hi guys,

Anyone here has done any kind of implementation of 9-DOF (or 6-DOF) IMU devices with PICs?

I'm trying to find something simple that can provide a heading, I believe I can do that with a magnetometer and other components (hence the 9-DOF) but many of them that I find online are discontinued.

So really, just testing the waters here to see who has had good success with such device - a recent one that is not discontinued - and what is the part number.

Unless you have other ideas... basically, I just want to point the circuit in one direction, set that as my 0 base, then if I rotate it on the Z plane (let's say 55 degrees to the left), then the device will know that it was rotated 55 degrees to the left.

Thanks!

Ben

Ttelmah · Joined: 11 Mar 2010 Posts: 19994

First thing to say is make sure you are looking at a 3.3v PIC. Though a lot
of the modules claim 3.3v and 5v operation, the PIC SPI, requires signals
to go to 0.8* the supply to be seen as 'high', and the chips usually cannot
guarantee this for a 5v PIC.
There is a driver for the ICM-20948 on GitHub. I'd suggest you look at
this.

benoitstjean · Posted: Wed Dec 03, 2025 11:38 am

Hmmmm.... not sure why that one didn't pop-up in my searches... The PIC24 on my circuit runs at 3.3V right now. I also have lever translators.

However, I don't like the fact that it says on DK website "Not For New Designs". Maybe there's a new replacement part.

Anyhow, I'll have a look.

Thanks!

Ben

benoitstjean · Posted: Wed Dec 03, 2025 11:59 am

I guess the library you are referring to on GitHub is for Arduino, not PIC?

Ben

Ttelmah · Joined: 11 Mar 2010 Posts: 19994

[url]
https://invensense.tdk.com/products/motion-tracking/9-axis/icm-20948/
[/url]
There are supply problems with the magnetometer wafers used in these.
The ICM-42670-P or the ICM-42688-P are the replacements. The former
is similar (9 axis), but the latter is only 6 axis.
The point is you'd need to start from the existing code, and modify it
yourself to suit the replacement sensor.

benoitstjean · Posted: Wed Dec 03, 2025 1:02 pm

Ah ok thanks for the heads-up.

But on Git-Hub, was there on in particular you were looking at?

Ben