I want to install openwrt on my RE305
I can only use TTL its a long story why
I am aware its 8/64 but I will not be installing much only setting up 802.11r
I have bought a 3.3v TTL adapter
I am new to TTL and don't really know where to start
I will be using windows 11
do I use something like putty or am I completely wrong here
yes, you do, but it's not required when flashing the RE305 v3.
It looks like V1 and V3 are supported. The V1 page has some information about how to connect the TTL/serial cable and I would imagine it's similar for V3. I guess first step is to figure out which version you have.
Also check the manufacturer's website for debricking instructions that will give you hints on how to flash.
Disclaimer- I don't have this device.
I have V3 so were do I start
do I setup TFTP to run over the serial line
I need some detailed instructions, I know a lot about technology, but this is new to me
last time I used openwrt I flashed though the stock interface
I don't have this device, so I can't help you with the details. 
My advice would be to look at the wiki pages I linked, as well as other similar devices. Either from the same manufacturer or with a similar SOC. This might give you hints on how to flash openwrt. A lot of router devices are similar enough that a lot of the same methods work among them. The hard part is knowing which one ones apply and which ones are dangerous. Again, I don't have this device, so I don't have the details.
does anybody else have any useful information
there are generic instructions but there not detailed enough for me
i have never done this before
V3 is supported.
For the first flash from factory firmware to OpenWrt use this file as firmware upgrade:
tplink_re305-v3-squashfs-factory.bin
For future upgrades from OpenWrt to OpenWrt use "*sysupgrade" images:
tplink_re305-v3-squashfs-sysupgrade.bin
how do I flash it with TTL serial and I think TFTP
thats all I am asking and not getting useful answers
The wiki links are all you need, if you're OK with flashing using your browser.
does anybody read anything
I have to use TTL and TFTP because the web interface will not allow the flash and gives me an error
I see no obviously locations for the serial console
What is the error? What file are you trying to flash? I think for the first flash, you need the factory.bin file, not the sysupgrade.bin file.
that was my issue in this case, but I also have a bricked RE200
Are you replying to me? I was asking about the error that you got when trying to flash. It might help to diagnose what the issue is.
Flashing the usual ways might be a better option in your case, because it looks like TTL/serial might be a very long shot. Look at the V1 photos in the wiki and you can see how clear the serial connection is. I agree, I don't see it in the V3 photos.
I know how to attach the TTL just not the software part
using factory.bin fixed my web flash
Got it. Now I understand what you meant about your issue.
just use putty.
so it's done/fixed ?
the RE305 is done, I did ask about my RE200 though
what do I run in putty
topic says 305
"openwrt serial flashing" @youtube.
its for all my device really
I have RE450 RE305 RE200
the RE200 is bricked from the ethernet cable falling out when going back to stock