100 /	P?S/8 WINCHESTER HANDLER
 110 
 120 /	P?S/8 NON-SYSTEM HANDLER FOR ANY (FIXED OR REMOVABLE) DISKS.
 130 
 140 /	LAST EDIT:	02-DEC-89	15:00:00	CJL
 150 
 160 /	COPYRIGHT (C) 1989 	CHARLES LASNER ASSOCIATES.
 170 
 180 /	THIS IS THE 128 WORD/BLOCK NON-SYSTEM HANDLER FOR HARD DISKS  ATTACHED  TO THE
 190 /	MDC8.  THE DISK STORAGE IS PARTITIONED INTO NAMED GROUPS OF 65,536 BLOCKS EACH
 200 /	OF  WHICH  IS CONTROLLED BY TWO HANDLERS.  HANDLER DETERMINATION IS CONTROLLED
 210 /	BY A  HANDLER  SET  BIT  WHICH  INDICATES  WHICH HANDLER IS IN EFFECT (0=LOWER
 220 /	HANDLER, 1=UPPER HANDLER).    EACH  HANDLER  IS  RESPONSIBLE FOR 32,768 BLOCKS
 230 /	BROKEN DOWN INTO 8  UNITS  OF  4,096 BLOCKS EACH, WHICH IS THE P?S/8 LIMIT FOR
 240 /	MINIMUM GRANULARITY HANDLERS.  THIS  IS  COMPATIBLE  WITH  NORMAL P?S/8 SYSTEM
 250 /	HANDLER REQUIREMENTS.
 260 /		NON-SYSTEM  HANDLERS ARE NORMALLY CONFIGURED TO ADDRESS THE SAME  DISK
 270 /	AREA  AS THE CORRESPONDING SYSTEM HANDLER, OR POSSIBLY A DIFFERENT  DISK  AREA
 280 /	THAN  THE  ONE  ASSIGNED  TO THE RUNNING SYSTEM ITSELF (SUCH AS  AN  ALTERNATE
 290 /	SYSTEM  CONFIGURATION  OR  FOREIGN  SYSTEM  RESIDING  ON  THE  SAME DEVICE) AS
 300 /	NECESSARY.   THE  USE  OF MULTIPLE NON-SYSTEM HANDLERS SUITABLY DEFINED ALLOWS
 310 /	DATA EXCHANGE, BACKUP/RESTORE,  ETC.   BETWEEN VARIOUS SYSTEMS RESIDENT ON THE
 320 /	SAME OR OTHER DEVICES.
 330 
 340 /	SUPPORTED HARDWARE:
 350 
 360 /	1)	CESI SCSI HOST ADAPTER (MINIMUM FIRMWARE REVISION 02).  ONE ADAPTER IS
 370 /		REQUIRED PER SYSTEM ATTACHED TO AS MANY AS EIGHT CONTROLLERS.
 380 
 390 /	2A)	OMTI 20-C, 20-D, OR COMPATIBLE  SCSI  CONTROLLER  (5X00  SERIES)  WITH
 400 /		PROPER DRIVES ATTACHED.
 410 
 420 /	2B)	SYQUEST  555  REMOVABLE  CARTRIDGE  (SQ400 TYPE)  WITH  IMBEDDED  SCSI
 430 /		CONTROLLER.
 440 
 450 /	OMTI  20-C, 20-D AND 5X00 (5100, 5200, 5300, 5400)  SERIES  CONTROLLERS   EACH
 460 /	SUPPORT UP TO TWO ST-506-COMPATIBLE DRIVES.
 470 
 480 /	REQUIRES PDP-8/I PROCESSOR (OR BETTER).
 490 
 500 /	THIS ASSEMBLY  PRODUCES  A  NON-SYSTEM  HANDLER  WHICH CAN BE CONFIGURED FOR A
 510 /	SPECIFIC HANDLER SET  WITHIN  ANY  NAMED  GROUP  ON  ANY PHYSICAL DRIVE ON ANY
 520 /	CONTROLLER ADDRESS (ID).   THE  HANDLER  WILL ADDRESS 32,768 LOGICAL BLOCKS OF
 530 /	CONTIGUOUS STORAGE ON THE DEVICE AS EIGHT UNITS OF 4,096 BLOCKS EACH.
 540 	EJECT
 550 /	CONFIGURATION CONSIDERATIONS.
 560 
 570 /	THIS ASSEMBLY SHOULD BE CONFIGURED FOR  THE  INTENDED  HANDLER REQUIRED BY THE
 580 /	USER'S SYSTEM.  THE FOLLOWING ARE PARAMETERS FOR CONSIDERATION:
 590 
 600 /	A)	GROUP - THE HANDLER  CREATED  BY  THIS  ASSEMBLY  ADDRESSES  HALF OF A
 610 /	DESIGNATED REGION OF 65,536 CONTIGUOUS  BLOCKS WHICH IS KNOWN AS A GROUP.  ANY
 620 /	GROUP SUPPORTS 8 MWORDS (8,388,608 WORDS)  OR  16  MBYTES  (16,777,216 BYTES).
 630 /	EACH HANDLER SUPPORTS 32,768 BLOCKS OF 128  WORDS  AS  EIGHT  HANDLER UNITS OF
 640 /	4,096 BLOCKS PER UNIT.  EACH UNIT THUS SUPPORTS .5 MWORDS (524,288 WORDS) OR 1
 650 /	MBYTES (1,048,576 BYTES).  TOTAL HANDLER SUPPORT IS 4 MWORDS (4,194,304 WORDS)
 660 /	OR 8 MBYTES (8,388,608 BYTES).  THIS IS THE UPPER  LIMIT  OF ADDRESSABILITY OF
 670 /	ANY INDIVIDUAL P?S/8 HANDLER COMPATIBLE WITH THE P?S/8 SYSTEM HANDLERS.
 680 /		TWO HANDLERS ARE USED TO ADDRESS THE  STORAGE  GROUP.    THE  SPECIFIC
 690 /	GROUP  CHOSEN WILL BE IDENTIFIED BY A CHARACTERISTIC  LETTER  ("A"-"Z")  WHICH
 700 /	WILL DETERMINE WHICH 8 MWORDS IS ADDRESSED BY THE  GROUP  OUT  OF  208  MWORDS
 710 /	(218,103,808 WORDS) OR 416 MBYTES (436,207,616 BYTES).  (THIS METHOD  PREVENTS
 720 /	ACCESS TO THE ADDITIONAL SPACE THEORETICALLY AVAILABLE ON THE DEVICE WHICH  IS
 730 /	HARDWARE-LIMITED TO  256 MWORDS (268,435,456 WORDS) OR 512 MBYTES (536,870,912
 740 /	BYTES).  THIS HANDLER MUST BE RE-WRITTEN TO ADDRESS THIS STORAGE IF REQUIRED.)