EDIT: We found the reason for this and it is a hardware issue. This question can be deleted as it is no longer valid.
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Hello,
We are currently developing a system that must use the ESB radio and SPI in parallel. We are noticing that when an ESB packet is received near (within 100us) of a SPI transfer taking place, the RSSI reading is significantly weaker (about 10dBm) than if the packet was received while SPI transfer was not happening.
Is it expected behaviour? If so, we may have to design our system around this which would increase complexity.
Thanks.