Revision 5 750's.

[Jim Gettys]

	Current production 750's are rev. 5, which adds the hardware
required for patching the control store.  Unmodified rev 5 machines
run 4.2 without change, without downloading any uCode.
	DEC's Unix Engineering Group have built code which downloads the
microcode at boot time (before unix is ever running) by reading a file
out of the root, NOT off of TU58 cartridge, which would be terribly
slow.
	We are also acting as field test for this code, and associated
uCode.  This uCode APPEARENTLY fixes the long standing copy on write
problem (the fault code is correct after CALLS on a write protected stack).
I do not know if the latest and greatest uCode fixes the TB parity problem,
or if it will be called Rev. 6.  The uCode has not yet been released to the
field.
	Questions should be referred to UEG.
				Jim Gettys
				Digital Equipment Corporation
				MIT/Project Athena
				decvax!mit-athena!jg