Is any of this decipherable to anyone?
https://forum.openwrt.org/t/support-for-archer-c50-v4/20174/10
https://forum.openwrt.org/t/support-for-archer-c50-v4/20174/11
https://forum.openwrt.org/t/support-for-archer-c50-v4/20174/13
It may provide more detail if stripping the header is required.
OpenWrt TFTP instructions for recovering C50v1 stock firmware mention:
To prepare the recovery file cut the first 0x200 (that is 512) bytes from original stock image. f you fail to follow this step you will brick your device, see.
dd if=orig.bin of=tplink.bin skip=1 bs=512
The router looks for the address 192.168.0.66 and a file named ArcherC50V1_tp_recovery.bin (non-windows users, ensure that the case match, specifically that V1 is capitalized in the filename).
Would this be the same for C50v3? Also, I extracted the following from oem firmware:
starting recovery...set serverip 192.168.0.66...tftp 0x80060000 tp_recovery.bin;erase tplink 0x20000 0x7a0000;cp.b 0x80080000 0x20000 0x7a0000...reset
This seems like TFTP recovery is used. I'm not sure about wtdwrite?