Hardware NSS signal conficts with PA15 mapped with GPIO output

Question

I'm having a Chinese development board of STM32F103RCT6 STM32_Mini_Pro where a winbond SPI flash is attached with SPI3. The Chip Select is attached with PA15 pin.

While configuring SPI in STM32 cubeMX, I assign Chip Select i.e. PA15 as GPIO output for software NSS.

But while assigning it i get an error like this

This is my assignment in Cube MX

What is the reason for this problem and how to rectify it?

Thank you

score 2 · Answer 1 · answered Jun 18 '18 at 12:01

2

There is no problem. Cube shows you that you can not assign slave select signal to PA15 (yes, it's rigth, you already mapped this pin as GPIO). Hardware slave select it STM32 micros has the meaning only if you use MCU as slave device.

answered Jun 18 '18 at 12:01

Alexey Esaulenko

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So i can use that pin as CS and continue?? – Devjeet Mandal Jun 18 '18 at 12:03
Of course. You can use this pin as conventional GPIO output, pull it down at begin of transer and pull up after last byte. – Alexey Esaulenko Jun 18 '18 at 12:31

Hardware NSS signal conficts with PA15 mapped with GPIO output

1 Answers1