Nucleo F091 SPI pins

[d_aliaga]

Posted on January 26, 2016 at 02:26

Hello.

I am looking at the Nucleo F091 pin distribution,

https://developer.mbed.org/platforms/ST-Nucleo-F091RC/

 and notice SPI1 and SPI2 pins. No problem about SPI2 pins (in fact I have used them successfully) but for SPI1 I can see that there are

two

 sets of pins for it. 

1) Is this correct?  I mean I see for example SPI1 MOSI is PA_7 and PB_5 .

2) Also I wonder which pin is SPI1 CS?? I am thinking PA_4 but then I read it is PB_6 so I am confused...

Any help will be greatly appreciated

#spi

[Tesla DeLorean]

Posted on January 26, 2016 at 03:08

There is a pin multiplexer, allowing peripheral signals to enter/exit via a subset of pins.

Check the Datasheet, there should be a pin list for Alternate Functions.

The Chip Select pin is often just a GPIO you can drive low/high, as the automated method offered by the peripheral usually doesn't mirror the requirements of the attached device.