Installation from serial console

[oieza67]

Hello to the community,

I'm trying to install u-boot on a microSD card from a serial connection using a USB to TTL adapter CH340 (exactly this one).

First I built u-boot from my Debian laptop using the board-specific official documentation, then I flash it on the microSD with the appropriate `dd` command : `

Code:

dd if=u-boot-rockchip.bin of=/dev/mmcblk0 seek=64 && sync

`

Then :
1. I set the microSD and plugged the dupont as recommended: GND on pin6, RX on pin8, and with without the TX on pin10.
2. Plugged the CH340, launched :

Code:

picocom /dev/ttyUSB0 -b 1500000

`
3. Power on

And... Nothing appeared.

I tried different combinaisons of dupont pluging, different built for u-boot but I didn't get any output.

What did I miss ?