i tried to updata a wr543 sometime last year from an low 24.10.x to the next 24.10.x.
the unit never came up and i had not the time to look at it.
now i wanted to start the recovery process but to my surprise the unit sticks in an u-boot loop saying the “BOARD IS NOT CALIBATED“ . so something has gone terribly wrong at update.
The big question would be if you have an ART backup (or full backup, from which you can extract ART) from your own router?
If you don't, it's game over for WLAN capabilities at this point - and considering age and feature set of the tl-wr2543nd not worth spending any money.
Keep in mind, we're talking about a 14 year old 8/64 ath79 device (AR7242, 400 MHz) with a single dual-band radio (so 2.4 GHz XOR 5 GHz), the second hand markets have better options starting around 5-15 EUR. Buying the means necessary for recovering (spi-nor writer, clamps, soldering equipment) quickly exceed that price range - and none of that gives you the required ART backup (from your own device).
Either you have a backup from your device, or you have nothing. ART contains wifi calibration data, which is generated specifically for your device during production to offset component variations. It can't be regenerated (without 6-figure measuring equipment and access to NDA'ed vendor tools).
You will need to ask that in tplink user forum because you need the config block from the device manufactured approximately at same time using same components, ie +/-1000 in serial number, the closer the better.
