My U7623 board just arrived and I am eager to get to work. I would like some clarification on the sysupgrade procedure for it. From the wiki:
- The U7623 comes with a vendor firmware based on OpenWrt 14.07. You can use the built-in sysupgrade functionality to upgrade to OpenWrt 21.02 or later using the “legacy” sysupgrade image...
Which appears to be this image:
unielec_u7623-02-emmc-512m-legacy-squashfs-sysupgrade.bin.gz, so far so good.
- Once running that, it is possible to sysupgrade again into the full (not 'legacy') image including new U-Boot, which gives use of all the system RAM and uses the partition table correctly.
This is where I am unclear. The only other unielec image on the 21.02.1 release download page is:
unielec_u7623-emmc-squashfs-img.gz. Do I use this for the second sysupgrade? Even though it's not marked as a sysupgrade image?
The reason I'm second guessing this, is that the snapshot download page appears to have two separate sysupgrade images. One marked legacy, and one not. Which is making me wonder if there should be a non-legacy sysupgrade image on the release page too?
I want to be extra careful, since my serial adapter is still on order so if I mess this up, it's two weeks before I can debrick it.
I don't have an answer for you, but I was just looking at the device on the website and it appears (visually, from what I can tell from that image) that it has a UART connection via a USB (micro-B) connector on the side opposite the ethernet ports. If I'm seeing that correctly, it may well have the USB-serial UART connection already included and you may only need to plug in a usb cable to connect it to your computer and open a serial terminal application to use the UART serial connection (you wouldn't need to serial adapter you have on order).
It is a USB UART indeed! Great eyes. And a fantastic board.
Awesome! Now you can do your upgrades with a little more confidence since the uart is accessible!
Answer is yes, can use unielec_u7623-emmc-squashfs-img.gz as the second sysupgrade image. I have clarified the wiki page to note this.
The wiki page was also unclear about where to get the preloader required for using the flash tool. It hinted that it was /dev/mmcblk0boot0, which as my subsequently bricked router will attest, is not the case. The preloader for Banana PI boards was available for download but not for this board.
I extracted the preloader from a mmcblk0boot0 image and have made it available for download. I also edited the wiki page with how to extract the preloader.
Who do I need to talk to about getting this file officially posted in the MT7623 section?