GRUB USB option

Link referenced.

I made a bootable micro SD with my Chromebook, Developer Mode, SeaBIOS and Legacy Boot. Boots okay.

Chromebook Ethernet port might not fit rtai criteria.

BRIX 1900 no SD ports but USB. Plugged micro SD into USB adapter, adapter to BRIX. Ubuntu desktop tool bar shows USB mount.

Include Mesa motion controller with Linux firmware via BRIX Ethernet. I'll try if works with Chromebook later. WiFi might have to get disabled.

Access GRUB, `c' and ls. Didn't show SD adapter to USB mounted with drive.
set root=(hd,1)(msdos1,sdb1)
chainloader +1
boot

A note displays not a bootable floppy pretty much. Default sent to grub rescue terminal.

grub rescue>exit

Automatically booted Debian, LinuxCNC and unexpectedly such a way but glad to access.

In-process of setting-up motion controller.

I'll try again with bootable USB later.

I thought the chainloader method earlier date wasn't working.

sudo update-grub might of made a menu.lst file and readable but didn't show USB mounted in GRUB menu.

Presently, on Debian desktop and Iceweasel browser at LinuxCNC Forum.

Actually idea was for USB to be in GRUB menu F2. Scripting if to boot device is okay for now.

I restarted Debian while SD to USB still plugged-in and default GRUB menu. Still no USB listed in GRUB menu.
`c'
grub>exit
Auto boot to Debian.

It depends on the boot file. An install boot disk seems not to work. Already installation and bootable does.