Instruction note on Yun Uboot Reflash tutorial


I was reflashing Uboot one more time after an unssucessful upgrade attempt from OpenWRT 1.5.2 to 1.5.3 and I noticed some of the instructions need to be updated if a user previously had 1.5.2 (or maybe an earlier one even?).

The tutorial in question is:

The step that needs a revision, or a special note to users above a certain version is this:

You'll need to do the next step quickly. Open the Serial Monitor from the Arduino IDE, press the YUN RST button (the white one near the LEDs), and press the Enter button a couple of times on your keyboard. If you're fast enough, you'll get something like the following in the Serial Monitor :
ATHRS26: s26 reset done
eth1 up
eth0, eth1
Hit any key to stop autoboot: 4 3 2
[Get Code]
The ar7240> is U-Boot prompt.

Pressing Enter several times was not working for me, instead the system now prompts you to type "ard" into the console if you want to access U-Boot prompt, so I tried that and was able to proceed with the rest of the reflash tutorial.

Hope this gets noted!



This only needs to be done if uboot itself has been reflashed (not recommended unless there is a good reason). Just doing a sysupgrade won't reflash uboot.

The only reason I can think of to reflash uboot is if you are disabling the console in inittab and have a sketch that may send on the serial port while openWrt is booting.

You can't reflash uboot unless your uboot is working and if you lose power during the uboot reflash your Yun is now a paperweight unless you unsolder the flash chip, reflash it with other methods, then resolder it.

Sure, makes sense. In my case I tried upgrading the openwrt vis sysupgrade only but something happened in the process that it didn't install 100% well and made the yun crash after that each time I reset. So i decided to reflash it. I understand this is an extreme case measure and I don't suggest others do it freely after reading this, just to be clear.