Why does EVE write (onto MISO) when being written to (on MOSI)?


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Referencing the attached o-scope printout (admin: this failed):

I'm writing via MOSI 128, 0, 0, 149 to the EVE. This command puts the value 149 into RAM_G's first address 0x000000. That's not the issue and that works fine.

The issue is the MISO signal is being simultaneously driven by the EVE. For the same four bytes I'm writing, it's sending back 0, 74, 67, 66. Why does it do this and/or what does this data mean? I'm concerned that this signal will happen when I'm using the SPI port for other peripherals beyond the EVE. I suppose if this MISO signal is not happening when I have CS+, then that avoids the problem, but I'm still curious about why the EVE would write at all.
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