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Topic: Can spi MOSI pin be idle low ? (Read 427 times) previous topic - next topic


When SPI enabled.

The MOSI pin seems to be idle high,
even I send a 0x00 through MOSI, it returns to HIGH.

is there anyway to make it low?


"The problem is in the code you didn't post."


Hi MorganS,

Thanks, but I am referring the MOSI pin, not the CLK pin.

When SPI peripheral takes over the MOSI pin,
it seems it let it park at High level which I want it to be low.


It seems to be part of the SPI protocol for MOSI, MISO and SS (or CS) to be normally high. Why do you need idle low?


You should not even be looking at MOSI anyway if your slave Select is not active.

SCK High or Low can be determined by the SPI Mode you are running:
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