Just starting this since the old thread was on the old openwrt forum. (https://forum.archive.openwrt.org/viewtopic.php?id=56737&p=1)
Someone made a bootloader for
http://xdd.co/router/pb-uboot-wndr3700v5.bin This one works perfectly and I can access the web recovery every time and boot an Openwrt sysupgrade file from the gui. To flash the bootloader itself: mtd_write write pb-uboot-wndr3700v5.bin Bootloader
You can flash Padavan firmware directly from this GUI. https://opt.cn2qq.com/padavan/
If you want to flash back to openwrt you need to use a script taken from here: But for WNDR3700v5 use the sysupgrade file as rootfs0.bin
Linux:
#!/bin/bash
if [ $# -ne 2 ]; then
echo Usage: $0 "kernel1.bin" "rootfs0.bin"
exit 1
fi
kernel1="$1"
rootfs0="$2"
[ -f "$kernel1" ] || { echo "kernel1 file doesn't exist, aborting: $kernel1"; exit 1; }
[ -f "$rootfs0" ] || { echo "rootfs0 file doesn't exist, aborting: $rootfs0"; exit 1; }
[[ ${kernel1##*/} =~ .kernel1.bin ]] || echo "first parameter must be kernel1.bin, aborting"
[[ ${rootfs0##/} =~ .*rootfs0.bin ]] || echo "second parameter must be rootfs0.bin, aborting"
tmpfile=$(mktemp tmp.XXXXXX)
truncate -s 8M "$tmpfile"
dd if="$kernel1" of="$tmpfile" conv=nocreat,notrunc status=none oflag=seek_bytes seek=0
dd if="$kernel1" of="$tmpfile" conv=nocreat,notrunc status=none oflag=seek_bytes seek=4M
cat "$rootfs0" >> "$tmpfile"
mv "$tmpfile" openwrt_for_breed.bin
echo "openwrt_for_breed.bin successfully created."
Windows:
@echo off
if "%~1" neq "" (echo %~1) else (goto help)
del /q /f openwrt_for_breed.bin >nul
del /q /f ~tempfile >nul
del /q /f ~kernel* >nul
set size=0
for %%I in (%1) do set/A size=4194304-%%~zI
fsutil file createnew ~tempfile %size%
copy /b %1+~tempfile ~kernel
del /q /f ~tempfile >nul
copy /b ~kernel+~kernel ~kernel1
copy /b ~kernel1+%2 openwrt_for_breed.bin
del /q /f ~kernel* >nul
exit
:help
echo.
echo.This will make OpenWrt binary file for using with Breed for Mi Router 3G.
echo.
echo Usage:
echo create_openwrt_for_breed.cmd {kernel1 file} {rootfs0 file}
echo.
echo Example: %0
echo create_openwrt_for_breed.cmd openwrt-18.06.0-ramips-mt7621-mir3g-squashfs-kernel1.bin openwrt-18.06.0-ramips-mt7621-mir3g-squashfs-rootfs0.bin
echo.
pause
A readymade file for flashing openwrt from the Pandorabox bootloader can be found here: (Openwrt 19.07.3). It'll probably work with at the Breed bootloader as well.
Someone made another bootloader: https://github.com/pinney/MT7621-u-boot-mod/blob/master/bin/MT7621S_uboot.bin It's supposed to have a web recovery too, but I never managed to access it.
There's also the Breed bootloader. https://breed.hackpascal.net/breed-mt7621-wndr3700v5.bin
But the web recovery is in chinese and I haven't tried it.
I'm running my Wndr3700v5 with 19.07.3 with the first mentioned bootloader. I does work fine on 2,4ghz. 5Ghz probably not. (It's not in use, more like a backup router).