I am trying to implement a circuit where 2 SPI drives (basically two masters) speak to 1 slave. Both operate on a 3 wire SPI.
Keeping that in mind I was going to have the CLK and MOSI of both as inputs (4 inputs), and would need 2 as output. A 4:2 multiplexer.
Was going to use CS, or some other signal to act the select signal to decide between which spi goes through.
Can't seem to find anything of the sort anywhere. Is there a different type of switch I should use?
I could add two 2:1 mux's together, but I'd much rather have 1 IC - space and cost is a premium for me.
edit: To make thing's clearer, the reason i would like to add a way of isolating the two masters is because one MCU turns on before the other by a couple of seconds. I am not entirely sure the default state for the MCU that turns on later. I would like to avoid the possibility where the second MCU tries to communicate whilst the first MCU is speaking to the slave device as they will both be share the same MOSI line.