blend micro SPI

[paul_tanner]

I want to access an SPI-only sensor device from a Blend Micro.

There is a need to avoid collisions between the two uses of the SPI port for the sensor and the nRF chip. I tried testing ble_busy() to see if I could avoid the conflict that way. However, that always comes back with true.

Is there a way to briefly use the SPI port without disabling BLE completely? If not I don't know why the Blend Micro brings out 4 pins for SPI.

This did not get an answer from RedBearLab other than to suggest use of ble_busy(). See redbearlab.zendesk.com/.../68357923-SPI-interference-with-BLE-connection

[David Edwin]

Sharing the SPI between the nRF8001 and other SPI slave devices is possible and many projects have successfully executed on that. However you do need to get control of the lines and not depend on a software that was not written for sharing the SPI lines.

You will need to get control of the SPI driver that is controlling the lines and as Hung stated, keep the REQN line high when controlling the other SPI slave device.

Related Questions: devzone.nordicsemi.com/.../

[paul_tanner]

Thx David,

It looks like this may be very difficult to fix given the way I am trying to build this using an Arduino IDE. On the Blend Micro the BLE-via-SPI stuff is not explicitly loaded but is pulled in automatically by the IDE. I therefore should look into other ways to do the build so the libraries can be adjusted.

However, I think I might be better off working directly with the nRF chip. The Blend Micro was supposed to be an easier way of doing this but I'm beginning to doubt that.

Regards, Paul