I just purchased the A20 Lime2 and have a 64gb MicroSD with Debian 3.4.90 release 2 (a20-lime2_debian_3.4.90_release_2.img) that I flashed in OS X El Capitan with the following command in terminal: "dd if=/pathtofile of=/dev/disk2 bs=1m). The A20 is connected to power via a StarTech USB to Barrel Type M 5V connected to a 5V power adapter - I've tried a few. The red PWR LED lights up and the ethernet lights come on. I cannot get the HDMI connected display to show anything - both displays I've tried just go into power saving mode. Any suggestions would be appreciated. Banging head against wall.
1. Fake SD card? Re-read and compare its image.
2. Use a debug lead for Lime's console tty to see how far it gets.
3. Sounds like your power is far too weak.
John
Try without specifying block size or use BS=4M
Best regards,
Lub/OLIMEX