DISCLAIMER: I'm not responsible for any damage caused by the following procedure!
!!! I do not know how to turn back to stock firmware. You have been warned !!!
I've put a clone of the openwrt repository with a custom branch named devolo-acr.
To build the image, follow procedure similar to https://openwrt.org/docs/guide-developer/toolchain/use-buildsystem
git clone --branch devolo-acr https://github.com/hmmmonteiro/openwrt.git
cd openwrt
./scripts/feeds update -a
./scripts/feeds install -a
make menuconfig
Choose:
Target System > (MediaTek Ralink MIPS)
Subtarget > (MT7620 based boards)
Target Profile > (DEVOLO ACR)
and save .config
make -j$(nproc) defconfig download clean world
go have a couple beers. it'll take a while.
You'll end up with and openwrt-ramips-mt7620-devolo_acr-squashfs-sysupgrade.bin, in openwrt/bin/targets/ramips/mt7620/ folder
Flashing:
Check the pinout schematics for the Edimax EW-7476RPC. They're the same. (Only RX, TX and GND. No VCC!)
ew-7476rpc-pcb, same as Devolo AC Repeater
Connect to the device through serial (Putty? 57600 baud)
Connect the device to your computer using an ethernet cable and assign your pc static address 192.168.1.2/24
Power your Devolo
Interrupt u-boot with option 2
Enter 192.168.1.1 IP for the device
Enter 192.168.1.2 for the PC
Enter the openwrt-ramips-mt7620-devolo_acr-squashfs-sysupgrade.bin filename
Wait 'till it flashes. It will reboot automatically into the new firmware. Give it time to install .. can take up to 3 or 4 mins.
You'll have access to shell either through serial or through ssh to 192.168.1.1 without password.
Configure network manually (/etc/config/network) and you'll be able to use opkg to install other software, like luci.
Although this is very recent, i've been using my Devolo for a few hours now and it seems to be handling things pretty well, including VLANs.
LEDs are not working (yet?).
Partitions could probably be better defined.
!!! I do not know how to turn back to stock firmware. You have been warned !!!