Artesyn MOTLoad Firmware Package User's Manual (February 2015) - Manual (Page 272)

Safe Start and Alternate Boot Image
MOTLoad Firmware Package User’s Manual (6806800C24D) 272
A user can determine whether MOTLoad is in Safe Start by observing the startup banner. Under
Safe Start, MOTLoad displays the string: "------SAFE START------" following the
Copyright context.
E.3 Alternate Boot Images
In firmware versions with Alternate Boot Image support, MOTLoad’s boot-loader code in the
primary boot block scans the flash bank for alternate boot images. If the boot loader finds an
image, the boot loader passes control to the image. An alternate boot image may be one of
three types: POST, USER, or Alternate MOTLoad. A POST image is a user-developed POST that
performs a set of diagnostics and then returns to the MOTLoad boot loader. A USER image is a
boot image; for example, the VxWorks boot ROM, that performs board initialization. A
bootable VxWorks kernel is also considered a USER image. An Alternate MOTLoad image is
intended to be an updated copy of MOTLoad firmware. Both a USER and Alternate MOTLoad
image are not required to return to the boot loader.
E.4 Firmware Startup Sequence
In firmware versions with Alternate Boot Image support, the firmware startup sequence
following board reset is to:
1. Initialize cache, MMU, FPU, and other CPU internal items
2. Initialize the memory controller
3. Search the active flash bank, possibly interactively, for a valid POST image. If found,
execute the POST image. If the POST image returns control to the boot loader, continue
the POST-image search.
4. Search the active flash bank, possibly interactively, for a valid USER image. If found,
execute the USER image. The USER image is not anticipated to return to the boot loader.
5. If a valid USER image is not found, search the active flash bank, possibly interactively, for a
valid MOTLoad image. If found, execute the Alternate MOTLoad image. The Alternate
MOTLoad image is not anticipated to return to the boot loader.
6. If a valid Alternate MOTLoad image is not found, continue with normal startup of the
pristine MOTLoad image in the primary boot block.