This device has previously been supported by the image
for Xiaomi Mi Router 3G v2. Since this is not obvious, the
4A is marketed as a new major revision and it also seems to
have a different bootloader, this will be both more tidy and
more helpful for the users.
Apart from that, note that there also is a 100M version of
the device that uses mt7628 platform, so a specifically named
image will also prevent confusion in this area.
Specifications:
- SoC: MediaTek MT7621
- Flash: 16 MiB NOR SPI
- RAM: 128 MiB DDR3
- Ethernet: 3x 10/100/1000 Mbps (switched, 2xLAN + WAN)
- WIFI0: MT7603E 2.4GHz 802.11b/g/n
- WIFI1: MT7612E 5GHz 802.11ac
- Antennas: 4x external (2 per radio), non-detachable
- LEDs: Programmable "power" LED (two-coloured, yellow/blue)
Non-programmable "internet" LED (shows WAN activity)
- Buttons: Reset
Installation:
Bootloader won't accept any serial input unless "boot_wait" u-boot
environment variable is changed to "on".
Vendor firmware won't accept any serial input until "uart_en" is
set to "1".
Using the https://github.com/acecilia/OpenWRTInvasion exploit you
can gain access to shell to enable these options:
To enable uart keyboard actions - 'nvram set uart_en=1'
To make uboot delay boot work - 'nvram set boot_wait=on'
Set boot delay to 5 - 'nvram set bootdelay=5'
Then run 'nvram commit' to make the changes permanent.
Once in the shell (following the OpenWRTInvasion instructions) you
can then run the following to flash OpenWrt and then reboot:
'cd /tmp; curl https://downloads.openwrt.org/...-sysupgrade.bin
--output firmware.bin; mtd -e OS1 -r write firmware.bin OS1'
Suggested-by: David Bentham <db260179@gmail.com>
Signed-off-by: Adrian Schmutzler <freifunk@adrianschmutzler.de>