TP-LINK TL-WR850N v1

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multiple revisions of this device, use caution
bgn (N300)
300Mbps Wireless Router
Homepage Product page
Support Support page
Wikipedia TP-Link
WikiDevi.wi-cat.ru TP-LINK TL-WR850N v1
3rd Party Firmware
dd-wrt Status Unknown
OpenWrt Supported
Tomato any flavor Incompatible
Gargoyle Status Unknown
Platform
BrandModelRev TP-LINK TL-WR850N v1.0
Model Part Number EN020-F5
FCC ID (fcc.io) TE7EN020FS
FCC ID (fcc.report) TE7EN020FS
Board ID 2050500859
Type wireless router
Series TL-WR850N
CPU1 checkY MediaTek MT7628NN
CPU1 Type MIPS 24KEc
CPU1 Speed 580 MHz
Flash1 Chip GigaDevice GD25Q64CSIG
Flash1 Size 8 MiB 8,388,608 B <br />65,536 Kib <br />8,192 KiB <br />64 Mib <br />0.00781 GiB <br />
RAM1 Size 64 MiB 67,108,864 B <br />524,288 Kib <br />65,536 KiB <br />512 Mib <br />0.0625 GiB <br /> (DDR2)
RAM1 Chip ESMT M14D5121632A-2.5B
ETH chip1 MediaTek MT7628NN
Switch MediaTek MT7628NN
Ethernet Port Count 1-100MbE-WAN
4-100MbE-LAN
Wired Standard IEEE 802.3i/3u

802dot11 OUI: none specified

Stock bootloader U-Boot
Stock FW OS Linux 2.6.36
Expansion IF types none specified
Power 9 VDC, 0.6 A
Connector type barrel
Serial Port (UART) yes, 4-pin header, J1, 3.3V TTL, (115200 8N1)
Other

Default SSID: TP-LINK_XXXX (47 addl. devices)
Default IP address: 192.168.0.1
the IP 192.168.0.1 is used by 826 additional devices
of which 110 are TP-LINK devices
Default login user: admin
Default login password: admin
admin:admin credentials used by 1353 additional devices
of which 283 are TP-LINK devices

Manuf/OEM/ODM TP-LINK
3rd Party Firmware Support OpenWrt • (List | Dev | DLs)
Retail
Availability End of Life
FCC approval date 02 August 2018
(Est.) release date August 2018
Country of manuf China
Radio 1
Chip1 MediaTek MT7628NN
Wireless interface OUI none specified
Antenna Connector Type none specified
MIMO status 2x2:2
Wireless Standard IEEE 802.11b/g/n
802.11n up to 300 Mbps
802.11g up to 54 Mbps
802.11b up to 11 Mbps
WiFi Operating Frequency 2.4 GHz
 CPU1 brandRadio1 chip1 brandRadio1 chip2 brand
TP-LINK TL-WR850N v1MediaTekMediaTek
TP-LINK TL-WR850N v2MediaTekMediaTek
TP-LINK TL-WR850N v3MediaTekMediaTek

For a list of all currently documented MediaTek chipsets with specifications, see MediaTek.

For a list of all currently documented TP-LINK devices with specifications, see TP-LINK.

300 Mbps - 2SS 2.4GHz 802.11n (40MHz chan.) = N300 class

Overview

"2050500859" and "1851" is silkscreened on the board.

Flashing

Flashing OpenWrt

Target: ramips
Subtarget: mt76x8
Package architecture: mipsel_24kc
Supported Since Commit
Support started version: 18.06.0
Current supported version: 25.12.2
LAN Hardware: MediaTek MT7628N
WLAN Hardware: MediaTek MT7628N
WLAN Comment: 2T2R 2.4 GHz
Installation method(s):
TP-Link TFTP, U-Boot TFTP recovery, see git-commit
Recovery method(s):
TP-Link TFTP, U-Boot TFTP recovery
git • >>
ramips: add support for TP-Link TL-WR840N v4 and TL-WR841N v13
TP-Link TL-WR840N v4 and TL-WR841N v13 are simple N300 routers with
5-port FE switch and non-detachable antennas. Both are very similar
and are based on MediaTek MT7628NN (aka MT7628N) WiSoC.

The difference between these two models is in number of available
LEDs, buttons and power input switch.

This work is partially based on GitHub PR#974.

Specification:

- MT7628N/N (580 MHz)
- 64 MB of RAM (DDR2)
- 8 MB of FLASH
- 2T2R 2.4 GHz
- 5x 10/100 Mbps Ethernet
- 2x external, non-detachable antennas
- UART (J1) header on PCB (115200 8n1)
- TL-WR840N v4: 5x LED (GPIO-controlled), 1x button
- TL-WR841N v13: 8x LED (GPIO-controlled*), 2x button, power input
  switch

* WAN LED in TL-WR841N v13 is a dual-color, dual-leads type which isn't
  (fully) supported by gpio-leds driver. This type of LED requires both
  GPIOs state change at the same time to select color or turn it off.
  For now, we support/use only the green part of the LED.

Factory image notes:

These devices use version 3 of TP-Link header, fortunately without RSA
signature (at least in case of devices sold in Europe). The difference
lays in the requirement for a non-zero value in "Additional Hardware
Version" field. Ideally, it should match the value stored in vendor
firmware header on device ("0x4"/"0x13" for these devices) but it seems
that anything other than "0" is correct.

We are able to prepare factory firwmare file which is accepted and
(almost) correctly flashed from the vendor GUI. As it turned out, it
accepts files without U-Boot image with second header at the beginning
but due to some kind of bug in upgrade routine, flashed image gets
corrupted before it's written to flash.

Tests showed that the GUI upgrade routine copies value of "Additional
Hardware Version" from existing firmware into offset "0x2023c" in
provided file, _before_ storing it in flash. In case of vendor firmware
upgrade files (which all include U-Boot image and two headers), this
offset points to the matching field in kernel+rootfs firmware part
header. Unfortunately, in case of LEDE factory image file which contains
only one header, it points to the offset "0x2023c" in kernel image. This
leads to a corrupted kernel and ends up with a "soft-bricked" device.

The good news is that U-Boot in these devices contains well known tftp
recovery mode, which can be triggered with "reset" button. What's more,
in comparison to some of older MediaTek based TP-Link devices, this
recovery mode doesn't write whole file at offset "0x0" in flash, without
verifying provided file in advance. In case of recovery mode in these
devices, first "0x20000" bytes are always skipped and "0x7a0000" bytes
from rest of the file are stored in flash at offset "0x20000".

Flash instruction:

Until (if at all) TP-Link fixes described problem, the only way to flash
LEDE image in these devices is to use tftp recovery mode in U-Boot:

1. Configure PC with static IP 192.168.0.66/24 and tftp server.
2. Rename "lede-ramips-mt7628-tl-wr84...-squashfs-tftp-recovery.bin"
   to "tp_recovery.bin" and place it in tftp server directory.
3. Connect PC with one of LAN ports, press the reset button, power up
   the router and keep button pressed for around 6-7 seconds, until
   device starts downloading the file.
4. Router will download file from server, write it to flash and reboot.

To access U-Boot CLI, keep pressed "4" key during boot.

Pictures

Retail Images
User Images