Not possible to use FRDM-STBC-AGM01 in SPI mode?

cancel
Showing results for 
Search instead for 
Did you mean: 

Not possible to use FRDM-STBC-AGM01 in SPI mode?

Jump to solution
706 Views
bhyland
Contributor I

I have been attempting to get the FRDM-STBC-AGM01 board functioning in SPI mode and have so far been unsuccessful. I worked through the instructions in "AN5167, Configuring the BRKT-STBC-AGM01 board for SPI Bus interface - Application Note" (which are out of date and need revision), and additionally removed the two I2C data line 4K7 pullup resistors.

I have no problems communicating with the FXAS21002C on the board, so the general connections and SPI drivers are fine.

I am aware that the data sheet for the FXOS8700CQ states that the part is only functional in point-to-point SPI, but there is no way to isolate that part from the gyroscope sharing the bus without destructively modifying the development board, which I would like to avoid.

Is there any way to get the FXOS8700CQ on the development board functioning via SPI without destructively modifying the board?

Secondly, has anyone got an example source code for communicating with the FXOS8700CQ via SPI so that I can confirm there is no issues with how I am setting up each R/W transaction and that the datasheet instructions are valid?

Thanks for your attention.

1 Solution
284 Views
bhyland
Contributor I

Update:

I have managed to communicate with the FXOS8700CQ on this board via SPI. The only way to do so is to cut the SA0_MISO1 trace between R7 and R2. Unfortunately this disconnects the FXAS21002C gyroscope so you can really only use one or the other on this board via SPI without even further modifications to break out the MISO line from the gyro to a spare pin.

View solution in original post

1 Reply
285 Views
bhyland
Contributor I

Update:

I have managed to communicate with the FXOS8700CQ on this board via SPI. The only way to do so is to cut the SA0_MISO1 trace between R7 and R2. Unfortunately this disconnects the FXAS21002C gyroscope so you can really only use one or the other on this board via SPI without even further modifications to break out the MISO line from the gyro to a spare pin.