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by anyfoo 676 days ago
But the AD936x is directly connected to the programmable logic (FPGA) of the Zynq, not the PS (CPU), so you can either do the bulk of your processing (e.g. filtering, demodulation, possibly higher parts of a protocol stack) in the FPGA, or, if you absolutely have to, let the FPGA pipe out raw IQ sample packets onto the Ethernet, because IIRC the Ethernet controller itself can also be routed into the FPGA using MDIO, no?

I haven’t tried this yet (despite owning an AntSDR E200), but that’s what the schematics of the AntSDR and my prior experience with Zynq suggests.

1 comments

You're right in that only the libiio firmware relies on the CPU to forward the samples out to the ethernet interface. The UHD firmware on the other hand does not seem to occupy the CPU to do this, however I have still had trouble getting transfer speeds to go much faster than they do with libiio (and I've had a lot of other problems with UHD personally). I'm not certain what could cause this limitation though.

In theory the hardware probably could do what you're describing if someone wanted to hack the FPGA internals themselves. I'd love to hear if you ever have any success getting things running better.