This device is NOT RECOMMENDED for future use with OpenWrt due to low flash/ram. DO NOT BUY DEVICES WITH 4MB FLASH / 32MB RAM if you intend to flash an up-to-date and secure OpenWrt version (18.06 or later) onto it! See 4/32 warning for details.
1) This device does not have sufficient resources (flash and/or RAM) to provide secure and reliable operation.
This means that even setting a password or changing simple network settings might not be possible any more, rendering the device effectively useless. See OpenWrt on 4/32 devices what you can do now.
2) OpenWrt support for this device will end after 2019.
19.07 will be the last official build for 4/32 devices. After 19.07, no further OpenWrt images will be built for 4/32 devices. See OpenWrt on 4/32 devices what you can do now.
Powered from AC electric wall-socket, so the USB port delivers 5V, 1A and can power and charge a device. Powering via micro-USB port requires modding.
You can see the exact version printed on a sticker on the outside of the device, right above the sticker with the MAC address and serial number.
Versions sold in European Union, Switzerland, & Turkey (“TL-WR710N(EU)”) have 4MB or 8MB flash. The 4MB Flash version is not recommended, there is only a short 100kB for additional applications free. An international/Chinese Version has 2MB flash only, which renders it unsupportable by OpenWrt. Good news is that it's possible to replace the flash chip with a bigger one.
Two cables can be soldered to the PCB under the cap called c207: red to square, black to round (tested on rev 1.2). The device can be powered up with 4 AA battery or a 1A USB (both tested).
Adding Micro USB to the device for USB power and Serial Port
With a Micro USB/UART adapter and the Battery Mod above, we can add a Micro USB port to the WR710N that can power the device and connect to its serial console. Tested successfully with this adapter board, powering the WR710N from the adapter's VBUS pad. A 2.5“ USB hard drive on the WR710N's USB host did not spin up, though.
Using an even smaller adapter board like this one, it might be possible to conveniently place the micro USB port between the WR170N's USB host and its LAN jacks, so that it's all in one box.
Pololu installed inside: the USB receptacle fits beautifully in between the ridges in the inside. Glue a piece of plastic on the back of the second ethernet connector to hold the adapter in place. Also glue a piece of plastic below and above the microUSB connector (in the ridge) to keep it from sliding up and down. Finally, the thickness of the router wall may be a little too thick for some microUSB connectors- they vary a little bit–you may need to bend back the tabs on the serial adapter's usb port to bring the connection closer to the wall.
Consider simply buying a GL.iNet 6416. Seriously, this is likely the device you actually want. And it's so cheap that it beats the time, trouble and money spend on modding - unless you do this for educational purposes…
standard SPI command use three address bytes (ie 24 bit), which is only sufficient to address a 16 MB space (0x1000000 = 16MB).
32+ MB chips use a different SPI command.
one (to be tested) option could be using a Winbond W25Q256 (32 MB) flash that a compatibility mode where the first 16 MB can be read/written using the 24-bit-address commands. Then there is a page selection scheme where 16 MB blocks are mapped into the 24-bit address space. As the bootloader needs to access the first few MBs, this flash chip might work with old bootloaders using 24 bit addressing. As long as the kernel is in that space, it should be able to boot it. Then the kernel will take over and it's routines would support the bigger SPI commands. It will also handle the loading of Wifi firmware from the ART partition at the end of the flash.
As seen above for 4 MB and 8 MB, the flash layout scales easily. U-Boot is in the first 128 KB, and ART is at the last 64 KB. The firmware partition in the middle scales for the flash size. So the 16 MB flash layout is:
16384 KB raw flash
mtd0u-boot 128 KB
mtd5firmware 16192 KB
mtd4art 64 KB
Build a new image
For a 16 MB flash add a new section in target/linux/ar71xx/image/Makefile, e.g.
The line $(Device/tplink-16mlzma) is the important part, as this tells the build to create a 16 MB image. And the whole build is smart enough to do the rest automatically. Thanks guys for making this scale so nicely.
The hardware ID 0x0710000F is also a random pick, the only constraint here is that it must not conflict with any existing values.
Put U-Boot, Firmware and ART into the new 16 MB flash.
Back to Original TP-Link Firmware
Original firmeware for TL-WR710N from original manufacturers website:
Version 1 ::
Size: 3.63 MB
Note: Configuration files will be erased.
If you want to revert back to stock TP-link firmware from custom firmware, most of the time you can not flash the TP-Link firmware directly from the official TP-Link website.
The reason for this is that most of the downloadable firmware from the TP-Link website contains a so called bootloader section in front of the actual firmware.
Normally when upgrading the official (not the custom) firmware this is fine of course, the official software on the router provided by TP-link takes the bootloader into account and handles or uses it properly so that your device keeps working.
However the custom firmware, like OpenWrt and DD-wrt (and probably others) only suspect an firmware image that doesn't contain a bootloader
and try to flash this extra data in the place of the spot in the memory where the firmware goes. That simply doesn't fit, resulting in a router that does not want to start up anymore.
toh/tp-link/tl-wr710n.txt · Last modified: 2019/10/16 13:21 by tmomas