I have not tried with the the x7 so maybe it doesn’t work yet? Will need to try myself to see if i can figure it out, although i don’t see why it’s not working. I will also try contact our frsky engineer to see if they know the secret to get this working.
However for now it might just be easier to update firmware on the x7 to be the EU lbt firmware
Can only post three replies, 3 questions, not the solution!? 
YES, Hero! it works. I did try it but with the crossed servo cable, with the straight one in the future use plug, it works perfectly.
Many thanks for sharing this!!!
Cannot post another reply (limit to 3 replies!?!), only edit this one, so hope you read this;
YES, Hero! it works. I did try it but with the crossed servo cable, with the straight one in the future use plug, it works perfectly.
Many thanks for sharing this!!!
Created an account just to reply to this post as i was having the exact same problem. I was trying to flash a X4RSB receiver with non-eu firmware using my Taranis X7, but to no avail. After several hours i started pulling my hair out, was about to give up when i decided to stick that damn servo cable into the “unused” TF port on the bottom of the radio. Pressed “flash ext. device” and to my gigantic surprise it started writing the firmware into my X4RSB. Unplugged, bound successfuly. Correct pin order is GND, +5V, SIG, as on the photo.
Had to create an account to thank you for this post. I was getting frustrated and started wondering if what FrSky call the “smart port” would work and was going to start poking around with my meter.
Saved me a lot of headaches, thanks.
I bricked 2 x4r-sb’s!
I read the responses and your Howto.
I followed it to the letter.
The first x4r is from China and wouldn’t bind. So I thought I needed to update. I did.
The progressbar started, red and green lights flickered, then it ended with the error “defice refused the update” I downloaded this firmware from FrSky:
X4RSP_EU_V21_build170322.hex.frk
Which should be the right one.
When I power up the receiver it’s completely dead. If I try to update it responds: no response, can’t update.
I thought I might have bricked it because I didn’t fully attach the connector to the Taranis. I tried again with my “old” receiver (chopped of the antenna’s, bought it in NL, never messed with the firmware). It bricked the same way. So I have 2 receivers bricked.
