wojtess

PROBLEM:
my tang nano 9k was having problems with uart under litex. It looks like problem with internal UART to USB converter.
pin 17 and 18(default used in `litex_boards/platforms/sipeed_tang_nano_9k.py` file) are connected to BL702,
so I assume that this is problem with proprietary software made my sipeed.

HOW TO FIX:
Change pins of UART and use external UART to USB module.
change `serial` pins in `_io` array.
to do this change lines from 34 to 39 to this:
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wojtess

ESP-IDF have exported function esp_err_t esp_wifi_80211_tx(wifi_interface_t ifx, const void *buffer, int len, bool en_sys_seq); It allows user to send raw ieee802.11 packets, it allows only certain types of packet.

To bypass check and send all packets you want you need to remove one call and replace it with mov instruction.

To use bypass copy "bypass.S" next to your "main.c", change CMakeLists.txt to something like this: idf_component_register(SRCS "main.c" "bypass.S" "other_c_files.c" INCLUDE_DIRS ".") and use esp_wifi_80211_tx_mod to send any packet you want using example code from bypass.c