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How to interact with Multiple slaves on SPI having different clock speeds

Hi, I want to connect 3 SPI slaves on the same SPI bus, But all slaves are working at different Clock frequencies and frame structures. What will be efficient way to communicate through SPI?

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  • If one slave has 8-bit and one have 16-bit, then it's likely that there are no messages that are meaningful to send to them both.

    Unless the data is actually laid out as 16-bit vales while one slave can't be configured for anything wider than 8 bits, so you need to do two 8-bit transfers (while keeping the slave select active) just to form 16 bits.

    Note that the slaves often doesn't see any time during a transfer, so they don't care much about # of bits configured, except that they split and present read data based on the configured width, and they expect the total message to be n times the number of bits. So you can't configure an SPI device for 15 bits and then send 16 bits without problems - that extra bit will be shifted in as start of one more words unless a reset can clear the

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  • If one slave has 8-bit and one have 16-bit, then it's likely that there are no messages that are meaningful to send to them both.

    Unless the data is actually laid out as 16-bit vales while one slave can't be configured for anything wider than 8 bits, so you need to do two 8-bit transfers (while keeping the slave select active) just to form 16 bits.

    Note that the slaves often doesn't see any time during a transfer, so they don't care much about # of bits configured, except that they split and present read data based on the configured width, and they expect the total message to be n times the number of bits. So you can't configure an SPI device for 15 bits and then send 16 bits without problems - that extra bit will be shifted in as start of one more words unless a reset can clear the

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