!		Bootstrap Help File - BOOT.HLP
!		Updated 1-May-1982, B. Peacock
!
!
!	This file describes the input parameters to the bootstrap program
!	VMB.EXE.  Normally the bootstrap will lookup the file SYSBOOT.EXE
!	in [SYSEXE] on the specified device, load it into memory and
!	transfer control to it.
!
!	Two sets of command files are provided on the VAX/VMS console floppy
!	to perform the necessary bootstrap operations.  One set of these
!	command files will boot selecting an option to stop in SYSBOOT to
!	alter system parameters.  They are invoked as console indirect
!	command files.
!
!		@DM0GEN			! Boot from RK07 unit 0
!		@DM1GEN			!		 unit 1
!		@DM2GEN			!		 unit 2
!		@DM3GEN			!		 unit 3
!		@DB0GEN			! Boot from RM03/RP06 unit 0
!		@DB1GEN			!		      unit 1
!		@DB2GEN			!		      unit 2
!		@DB3GEN			!		      unit 3
!		@DB4GEN			!		      unit 4
!		@DB5GEN			!		      unit 5
!		@DB6GEN			!		      unit 6
!		@DB7GEN			!		      unit 7
!
!	The other set of these command files is normally invoked only via
!	the BOOT command but may be invoked explicitly as indirect command
!	files.  These command files perform a normal, non-interactive boot
!	without any stop in SYSBOOT to change parameters.
!
!	BOOT DM0   or	@DM0BOO.CMD	! Boot RK07 unit 0
!	BOOT DM1			!	    unit 1
!	BOOT DM2			!	    unit 2
!	BOOT DM3			!	    unit 3
!	BOOT DB0			! Boot RM03 or RP06 unit 0
!	BOOT DB1			!		    unit 1
!	BOOT DB2			!		    unit 2
!	BOOT DB3			!		    unit 3
!	BOOT DB4			!		    unit 4
!	BOOT DB5			!		    unit 5
!	BOOT DB6			!		    unit 6
!	BOOT DB7			!		    unit 7
!
!	The bootstrap is loaded into memory at least one page above the first
!	available working memory to allow space for the Restart Parameter
!	Block.  The address of the base of the bootstrap is passed through
!	SP, the stack pointer, where it also serves as a temporary stack
!	pointer.
!
! Input Parameters:
!	R0  -  Boot Device Type Code (RPB$B_DEVTYPE)
!	       <07:00>	
!			0 => Disk Pack		(RM03/RP04/RP05/RP06/RP07)
!			1 => Cartridge Disk	(RK06/RK07)
!			2 => RL01/2
!			3 => IDC on 11/730
!		       17 => UDA-50
!		       32 => CI
!		       64 => Console Block Storage Device 
! 	       <15:08> Reserved for future expansion
!	       <31:16> Device Class Dependent (RPB$W_ROUBVEC)
!		       Unibus  - optional vector address, 0 implies use the 
!				 default vector		 	
!		       Massbus - N/A	
!	R1  -  Boot Device Bus Address
!		11/780 and 11/730
!			<31:04> MBZ
!			<03:00> TR number of the Adaptor
!		11/750
!			<31:24> MBZ
!			<23:00> Address of the I/O page for the Boot Device
!				Adapter
!
!	R2  -  UNIBUS:
!			<31:18> MBZ
!			<17:03> Offset UNIBUS Address of Control Register
!			<02:00> MBZ
!
!	       MASSBUS:
!			<31:04> MBZ
!			<03:00> Controller/Formatter Number
!	
!	       CI:
!			<31:08> MBZ
!			<07:00> HSC Port Number (Station Address)
!	
!	R3  -  UNIT
!			<31:04> MBZ
!			<03:00> Unit Number
!	R4  -  Logical Block Number to read as boot block (N/A on 11/750)
!
!	R5  -  Software Boot Control flags
!		Bit	Meaning
!		---	-------
!		 0	Conversational boot. At various points in the system
!			boot procedure, parameter and other input will be
!			solicited from the console.
!
!		 1	Debug.  This flag is passed through to VMS and causes
!			the code for the exec debugger to be included in
!			the running system.
!
!		 2	Initial breakpoint. If this flag is set, and the exec
!			debugger code is included (set bit 1) then a breakpoint
!			will occur immediately after the exec enables mapping.
!
!		 3	Boot block.  If this flag is set then the boot block
!			will be read and control transfered to it.
!
!		 4	Diagnostic boot.  This flag causes a boot by file
!			name for the diagnostic supervisor.
!
!		 5	Bootstrap breakpoint. This flag causes the bootstrap
!			to stop a breakpoint after performing necessary init-
!			ialization if it has been built with debug code.
!
!		 6	Image header. If this flag is set the transfer address
!			from the image header of the boot file will be used.
!			Otherwise control will transfer to the first byt of the
!			boot file.
!
!		 7	Memory test inhibit. This flag inhibits the testing
!			of memory during bootstrapping.
!
!		 8	File name. Causes the bootstrap to solicit the name 
!			of the boot file.
!
!		 9	Halt before transfer.  Causes a HALT instruction
!			to be executed prior to the transfer to the bootfile.
!			This option is useful for debugging purposes.
!
!		10	No PFN Deletion, Not Implemented
!
!		11	Specifies Multi-port memory is to be used for the total
!			executive memory requirement. No local memory is used.
!			If bit <5> is also on, Diagnostic Supervisor will enter
!			"autotest" mode.
!		
!		12	Specifies that the multiport memory should be used in
!			addition to local memory as single memory.
!
!		13	Specifies more exahustive test of memory to locate un-
!			correctable errors.
!
!		14	Specifies request to use multi-port memory if MS780
!			memory is insufficient to support the system. 11/782 
!
!		<31:28> Specifies the number of the top level directory on sys-
!			tem disks with multiple operating systems.
!
!	SP  -  ADDRESS+(^X200) of first working 64Kb memory region
!	       usable as both stack pointer and pointer to good memory.
!
!
! Output Parameters:
!	R10	-	Base address of region containing secondary bootstrap
!	R11	-	Pointer to Restart Parameter Block (RPB)
!	SP	-	Stack pointer
!	PR$_SCBB - 	System Control Block base register
!
!	Memory layout at start of secondary bootstrap:
!
!	+-----------------------------------------+ :BASE
!	!					  !
!	!	Restart Parameter Block (RPB)	  !
!	!					  !
!	+-----------------------------------------+ :BASE+^X200
!	!					  !
!	!	Primary Bootstrap Code		  !
!	!					  !
!	!					  !
!	+-----------------------------------------+ :PR$_SCBB
!	!					  !
!	!	   System Control Block		  !
!	!					  !
!	+-----------------------------------------+ :PFNMAP
!	!					  !
!	!		PFN Bitmap		  !
!	!					  !
!	+-----------------------------------------+ :PFNMAP+^X800
!	!					  !
!	!	     Bootstrap Stack		  !
!	!					  !
!	+-----------------------------------------+ :(SP)
!	!					  !
!	!	 Secondary Bootstrap Code	  !
!	!					  !
!	+-----------------------------------------+
!
