rick@snowhite.cis.uoguelph.ca wrote:
>>> We'll need to know that so we
>>> can figure out what type of DEC controller it emulates, which in turn
>>> will determine how we'll try to boot the machine.
>>>       
> As far as I recall, the boot firmware only knew about MSCP, so nothing
> else could be booted. (ie. Anything else had to boot off floppy or tape
> to get it going.) There wasn't much to the boot command:
>   
Some of the Emulex, (and other off-brand controllers), included a diag 
and/or boot
ROM program. The CPU did not support a direct command like ">>> boot rm05",
but you could boot by entering a few numbers in the memory/registers and 
running
the ROM program. The KA630 only supported booting MSCP, TMSCP, and ethernet.
The SC03 has a boot ROM option, (see 3.4.4.2), but I expect it did not 
support
VAX, only pdp11. These older controllers required that you deposit command
numbers in the controllers registers. Often one command could DMA the
boot block into RAM, then you just run that location. But the VAX
may require an extra step to map memory pages using the MMU before you issue
the DMA command. So a user could have a set of commands that would be
entered to boot the off-brand controller.

The Emulex SC03 document can be found at:

http://bitsavers.org/pdf/emulex/SC0351002-J_SC03tech_Nov84.pdf

A good example of setting the MMU can be found in the Emulex QD21
documentation in 4.7.3:

http://bitsavers.org/pdf/emulex/QD2151002-J_QD21_Jun90.pdf

 >>>I                         !BUS INIT
 >>>D/P/W 20001F40 20         !ENABLE MEMORY
 >>>D/P/L 20088000 80000000   !SETUP MAP 0
 >>>D/P/L 20088004 80000001   !SETUP MAP 1

The SC03 documentation seems to include the details needed to write a VAX
boot loader for this controller, but it may be easier to boot over the 
ethernet
using a MOP server.

Todd