Hello,
I tried to replace the SD card with an SD card shaped EMMC key (not EMMC module) but u-boot cant find any bootable patition despite using tha same ubuntu image. While this works flawlessly with raspberry pi the rock 5b seems to have big trouble with those keys. Does anybody know how to fix this?
What car do You have? raspi key? or eMMC via micro sd adapter?
Those are just problematic and don’t work on every card reader, easiest solution is still to use good micro sd card. eMMC speed is limited via sd card interface so don’t bother with that when You can have about 3x better with eMMC or 15x better on nvme, which happens to be sometimes cheapest of them.
I used one of those raspi keys. Today I learned at an other project, that these raspi keys really differ from regular SD cards regarding initialization process. I thought they are just an in-place replacement.
So I guess the problem is solved at this point.
Because they advertise them like it’s expensive and durable alternative.
I also have them and quickly learned same thing. It works for restricted number of devices (I think older devices), so You need to pay extra attention for compatibility.