OpenWRT for TP-Link MR200v1

Follow all steps at own risk!

Before downloading anything, consider reading the blog post:

https://peterbabic.dev/blog/how-verify-openwrt-integrity-files

Recovery image preparation

The recovery image is used to replace the stock firmware with OpenWRT via TFTP. Citing the MR200 OpenWRT manual:

Turn on the device while pushing the WPS button until the WPS light turns on. At that point, the bootloaders integrated tftp client with the ip address of 192.168.1.1, tries to connect to a tftp server running at address 192.168.0.66 and getting the file named ArcherC2V1_tp_recovery.bin. so you need to be running a tftp server with the ip/netmask of 192.168.0.66/23 and connect it to lan port1. It is vital that your firmware includes the bootloader at the very beginning (without any extra tp-link header) as the bootloader will start writing the firmware to flash with the starting address of 0x00000000.

Manual recovery image preparation:

cd firmware
dd bs=512 obs=512 skip=1 count=256 if=Archer\ MR200v1_0.9.1_1.2_up_boot_v004a.0\ Build\ 180502\ Rel.53881n.bin of=ArcherMR200_bootloader.bin
cat ArcherMR200_bootloader.bin openwrt-19.07.6-ramips-mt7620-ArcherMR200-squashfs-sysupgrade.bin > ArcherC2V1_tp_recovery.bin

Manual recovery image upload using TFTP:

sudo pacman -S atftp
sudo mkdir -p /srv/atftp
sudo cp firmware/ArcherC2V1_tp_recovery.bin /srv/atftp
sudo chown -R atftp:atftp /srv/atftp
sudo ifconfig enp0s31f6 192.168.0.66/23
sudo systemctl start atftpd.service
# Optionally test TFTP server is working properly
#curl -O tftp:/192.168.0.66/ArcherC2V1_tp_recovery.bin

Revert to TP-Link stock firmware

Important: Always revert back to the same version in which you switched from.

cd firmware
dd bs=512 obs=512 skip=257 count=15744 if=Archer\ MR200v1_0.9.1_1.2_up_boot_v004a.0\ Build\ 180502\ Rel.53881n.bin of=extracted_firmware.bin
scp extracted_firmware.bin root@openwrt:/tmp
/usr/bin/ssh root@openwrt
mtd -r write extracted_firmware.bin firmware

4G signal LED integration

OpenWRT does not enable working LED's for 4G signal by default. Manual method:

cd files
scp -r root etc root@openwrt:/
/usr/bin/ssh root@openwrt
opkg update
opkg install curl
reboot

Custom image with built in LED signal integration

Manual custom image build steps:

pacman -S --needed base-devel ncurses zlib gawk git gettext openssl libxslt wget unzip python
wget https://downloads.openwrt.org/snapshots/targets/ramips/mt7620/openwrt-imagebuilder-ramips-mt7620.Linux-x86_64.tar.xz
tar xJf openwrt-imagebuilder-ramips-mt7620.Linux-x86_64.tar.xz
cd openwrt-imagebuilder-ramips-mt7620.Linux-x86_64
ln -s ../files .
make image PROFILE=tplink_archer-mr200 PACKAGES="curl" FILES=files/

The sysupgrade file is available at openwrt-imagebuilder-ramips-mt7620.Linux-x86_64/bin/targets/ramips/mt7620/openwrt-ramips-mt7620-tplink_archer-mr200-squashfs-sysupgrade.bin after the build and includes curl and the LED script.

Alternatively, the steps are automated in a script. After running, the custom image file is conveniently symlinked to mt7620.

Credit

The authors of the LED script are users asenac and spamcop, published ad OpenWRT forum