all things go step by step , so i think . Rs232c -> HDMI console -> HDMI X
once the openbsd system is installed to the arm bord , i only use ssh to the bord insted of RS232c . it is a very good property becase the door (for example) controlled by the board will not need both monitor and keyboad . the problem is security itself . sshd controlled by ida or rsa is essential , so i think . ----- regards