User`s manual

4.4 Flash ROM (System ROM)
Table 4–2 (Cont.) Special Header Entry Descriptions
Entry Description
Decompression flag The decompression flag informs the SROM code whether
the the ROM image was compressed. The SROM code
contains routines that execute the decompression algorithm.
Other compression and decompression schemes, which work
independently from this scheme, may be employed.
Destination address This quadword contains the destination address for the
image. The SROM code will load the image at this address
and begin execution.
Firmware ID The firmware ID is a byte that specifies the firmware type.
This information facilitates image boot options necessary to
boot different operating systems.
Firmware Name
Firmware
Type Firmware Description
Debug monitor 0 Alpha evaluation board
debug monitor
Windows NT 1 Windows NT firmware
Alpha SRM 2 Alpha System Reference
Manual console
Header revision The revision of the header specifications used in this header.
This is necessary to provide for changes to the header
specification. Version 0 headers are identified by the size of
the header (32 bytes).
Flash ROM image size The flash ROM image size reflects the size of the image as
it is contained in the flash ROM.
Optional firmware ID This optional field can be used to provide additional
firmware information such as firmware revision or a
character descriptive string up to 8 characters.
Header checksum The checksum of the header. This is used to validate the
presence of a header beyond the validation provided by the
validation pattern.
4.4.2 Flash ROM Structure
The Alpha PCI 64–275 loads and boots the first image (the debug monitor)
during the power-up and initialization sequence if the BOOT_OPTION jumper
J3-25/26 is not installed.
Functional Elements 4–9