802.15.4 between RF233 and nrf52840 radios fails

[hudson-ayers]

Previous tests (see #1341) have showed that 15.4 userspace apps (examples/tests/ieee802154/radio_{tx, rx}) work between two nrf52840dk boards, but these tests do not work between an nrf52840dk and an Imix.

Note: I tested with both boards configured to use the same channel (26), bitrate (250kbps), PAN (0xABCD), and frame version (V2006).

Nrf --> Imix fails, with the Imix never indicating it has received packets at all.

Imix --> nrf fails. The nrf does receive the PHY layer frames, but the awakeMac fails to decode the headers in these packets. The header decoding is completed in a series of macros so tracing through the failures is difficult, but the failures seem to change with each consecutive packet, which is surprising to me.

[hudson-ayers]

Update: Pretty sure the issue is with the nrf52840 15.4 implementation, because when I configure a second nrf as a sniffer using nordics "Nrf sniffer for 802.15.4" , it correctly receives and parses 15.4 packets sent by an Imix, but not those sent by an nrf52840dk running the same Tock app.