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Correct SPI interfaces in the Nucleo Arduino figure?

18 Aug 2014

On the page for the ST Nucleo L05R8 board there is a figure that shows the pinouts and usable peripherals for Ardiono and Morpho:

The question I have relates to the figure for the Arduino shield and SPI:

Looking at the right hand side with CN5 and CN9 connectors it seems that SPI1 is available in both CN5 and SN9. But no SPI2. Is this correct, or should 'SPI1' for CN9 in fact be SPI2?

Yours JoachimS

16 Nov 2014

Hi JoachimS,

Surprised no one has answered you here, but the diagram is correct, SPI1 on CN5 maps to pins PA5, PA6, PA7 which are SPI1 ports when those pins are set for Alternate Function 1 (AF1), and on CN9 map to pins PB4, PB5, and PB3 which are SPI1 when set to alternate function 1. That makes it possible to use them as Analog in pins and still keep the SPI functions available.

Or said a different way, you can make each pin for SPI1 (MOSI, MISO, SCLK) appear *either* on CN5 or CN9 but not both, you can also split them and have MISO on CN5 and MOSI on CN9 for example.