L3GD20 not working with TI Digital Signal Processor

Hello all;

I am working on this sensor since some time but as I am new to this field of work, I am facing some problems in running this sensor.

Can anyone guide me on this? I have got the driver and header files from the supplier. I am using a TI Digital Signal Processor.

Please help me in this regard. Thanks for your time. Your help and support is appreciated.

Regards,
Irfan.

Hi, Irfan.

I am sorry you are having problems. Could you please be more specific about what problems you are having?

-Derrill

Hi Derrill sir,

Firstly, thank you for your quick response.

To start with, I have to test this sensor for space applications. So, I have an Digital Signal Processor (DSP-from Texas Instruments-starter kit TMS VERSION) With me for testing these kind of sensors. I have the example codes from the DSP as well as the ST company offered a set of codes as the sensor drivers (one is a header file and other is the main source driver code).

I am very much new to these kind of electronics. I am confused and actually not understanding how exactly I can join these codes and get some signals out of this sensor. I need a guidance in how exactly can I start off to achieve the proper working of this sensor.

Please help me in this regard.

Regards,
Irfan.

[quote=“Derrill”]Hi, Irfan.

I am sorry you are having problems. Could you please be more specific about what problems you are having?

-Derrill[/quote]

You are clearly in way, way over your head. My suggestions would be to:

  1. read the data sheet for the L3GD20 very carefully, also making sure that you understand how I2C communications work.

  2. buy an Arduino and use the sample code that Pololu provides to get going. From their description of the device:

[quote]Sample Code

We have written a basic Arduino library for the L3GD20 that makes it easy to interface this sensor with an Arduino. The library makes it simple to configure the L3GD20 and read the raw gyro data through I²C.[/quote]

  1. Before you move on to the TI DSP, make sure that you understand what every line in the Pololu example code does, and what the equivalent for the TI processor would be.

PS: Space applications? Any chance you are working for Kim Jong-un?

Hi john,

Thank you for your advise. I have noted the contents properly. But I have to make it for SPI mode.

I have an mega2560 arduino. I will use it but ultimately I need to use the TI DSP for my further experiments.

No. I don’t work for the person you mentioned.

Thanks!

Regards,
Irfan.

Oops sorry! Mr. Jim.

Also, what could be the procedure if I would like to use the same for SPI?

As I plan to work for SPI first.

Regards,
Irfan.

Get it to work first, using an MCU and I2C code that is known to work, then figure out how to interface using SPI.

Thank you sir. I will get back to you soon.

Regards,
Irfan.

Hi sir,

I am back. I tried the codes as they are given in the library. everything goes well untill this error crops in as attached in the file below. Please help me in this regard.

Thanks a lot!

Irfan.


Hi, Irfan.

It looks like you have not installed the L3GD20 library correctly. You can find the L3GD20 library here.

-Derrill

Dear Derrill sir,

I got it cleared but there is lot of scrap data in between the actual data like (-1 -1 -1) so many times repeated. Will this problem be solved using an efficient moving average method?

Also, do you know anything about the library for ADIS16405 IMU from Analog devices.?

Thanks a ton for your continuous replies. I am grateful to you sir.

Regards,
Irfan.

Are you running an unmodified version of our example code? You should not be getting any junk data with our example. Using a moving average should work fine for filtering the data once the issue with junk data is fixed.

I am not familiar with the ADIS16405 IMU or its library.

-Derrill

I think I am using the unmodified version. can you please guide me to the modified version of the code.?

Regards,
Irfan.

Also, to inform you that presently I am using an evaluation board from STMicroelectronics (STEVAL-MKI107V2). The picture attached.

Please help me in this regard sir.

Regards,
Irfan.

Hello again Mr. Derril & Mr. Jim,

I have tried so many times but I have the same problem as shown in the attachment. I can read the data on monitor but not continuously.

Please help me in this regard.

Thanks,
Irfan.

Are you using our L3GD20 carrier board?

-Derrill

No sir.

I am presently using an evaluation board from STMicroelectronics (STEVAL-MKI107V2). The picture attached.

Please help me in this regard sir.

Regards,
Irfan.

Derril sir,

Do I need to buy Pololu version of the L3GD20 or the library still works with my board shown in the picture above?

Please advice as I am running out of time.

Regards,
Irfan.

Derrill sir,

Yes. I clear the concern. The codes works fine now.

Can anyone suggest me what could be the best form of Moving average filter to implement?

Regards,
Irfan.