Very simple SPI Code

RE: Very simple SPI Code

Annim — Fri, 19 Dec 2014 10:49:15 GMT

Yes, please, add spi_master.h on your main.cpp and in libraries tree, add spi_master.c .

RE: Very simple SPI Code

Julian — Fri, 19 Dec 2014 10:37:29 GMT

Thank you for your advice. Am I correct in assuming that you used spi_master.cpp from the Nordic SDK library? I only ask this because I added it to my project and your code contains no #include statements and I am getting A LOT of compile errors.

RE: Very simple SPI Code

Annim — Thu, 18 Dec 2014 06:43:42 GMT

Please try out my sample code here posted. It is on adxl345 actually. It worked for me and its pretty much straight way. Hope this should work for you.

devzone.nordicsemi.com/.../

RE: Very simple SPI Code

Julian — Tue, 16 Dec 2014 18:49:14 GMT

Yes. I modified the loopback example to fit the PCA10001 board and it worked fine, but I could not get it to work with the ADXL345. I also tried examples from RedBearLab but to no avail. A major factor is probably my limited knowledge about event handling. that is why I wanted something REALLY SIMPLE that would also serve as learning curve for me.

RE: Very simple SPI Code

Stefan Birnir Sverrisson — Tue, 16 Dec 2014 14:59:58 GMT

Hi Julian

Have you looked at the SPI examples in the nRF51 SDK?

Update 17.12.2014 I do not have something really simple SPI set up, but I think it should be possible to do it in these steps:

Initialize the SPI master, similarly as is done in the spi_master_init function in the spi_master_example.
Define the SPI IRQ handler and initialize it.
Write a byte to TXD

Anyway I think the easiest way to move forward is to use the SPI driver in perhaps a more simple way than the SPI loopback example does:

Define an event handler in your main function
create RX and TX buffers and initialize them with data
Initialize the SPI_0 master by calling spi_master_init with the name of the event handler you defined
Call spi_send_recv function to send and receive data on the SPI
Monitor your configured SPI pins with a logical analyzer or oscilloscope.
First step is to see the clock signal on CLK pin and your TX data clocked out on MOSI pin.
Next step would be to loop that data back into the MISO pin and check the RX buffer