boot.delay: 0 (User key press delay) boot.gpio: 0 (Boot/Download select gpio) boot.sel: 0 (0=Use Serial 1=Use gpio for boot/download select) boot.dl: 0 (Download IMAGE by default action when sel=0) boot.silent: 0 (In silent mode bootloader does not output anything) boot.dltype: 0 (0=Download via Ethernet,1=Download via USBC,2=SDCard Download) boot.breakchar1: 0x00000020 (1st Char used to enter Bootloader Menu) boot.breakchar2: 0x00000000 (2nd Char used to enter Bootloader Menu) boot.breakchar3: 0x00000000 (3rd Char used to enter Bootloader Menu) boot.breakchar4: 0x00000000 (4th Char used to enter Bootloader Menu)
Delay time while booting to detect user action. The value is in seconds. If you can't enter the Bootloader Menu because the Colibri doesn't detect the character over the serial port, make this delay longer.
This value is only active if boot.sel = 1.
Then you can choose a GPIO number which defines if the Bootloader starts normal (GPIO Low) or if it enters the download mode (GPIO High).
If the GPIO is Low, the bootloader ignores all input over the serial port.
If the GPIO is High, you can use the breakchars to enter the bootloader menu, before the bootloader begins with the automatic download.
If you set boot.sel=1 you can choose a GPIO to switch between boot and download mode. See also the comments to the boot.gpio value.
This value is only active if boot.sel=0.
If you set boot.dl=1 the bootloader will automatically try to download a image. The image needs to be an uncompressed OS image. It will be loaded into RAM.
Choose the download type. See also: USB image download
If the bootloader receives characters mentioned below over the serial port, it will enter the bootloader menu. The breakcharacters have to come in the right order.
First breakchar1 then breakchar2 ....