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From: las...@watsun.cc.columbia.edu (Charles Lasner)
Subject: Teeny Tiny RX01 Bootstrap
Message-ID: <1993Mar29.171612.23495@news.columbia.edu>
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Reply-To: las...@watsun.cc.columbia.edu (Charles Lasner)
Organization: Columbia University
Date: Mon, 29 Mar 1993 17:16:12 GMT
Lines: 44

By popular demand, here is the tiny bootstrap for the RX01.  It is for drive
zero only, does not retry indefinitely, depends on the "kerclunka" self-test
to do the reading for it, and is either for actual RX01 or compatible, or
for RX02 set for RX01 mode only.

There are only 13 significent words to load, and a bunch of zeroes in a row
(which must be 0000) and one don't care location (a subroutine header) which
can be loaded with the previous or next location's contents to save a switch
setting operation, etc.

/	TINY RX01 DRIVE ZERO ONLY BOOTSTRAP.

			*33			/STARTS LOADING HERE

00033	6755	SHANGG,	SDN			/BOOTSTRAP STARTS HERE; DONE FLAG UP?
00034	5054		JMP	SLODE1		/TRY TRANSFER FLAG IF DONE FLAG IS NOT UP
00035	7326		NL0002			/SETUP FOR EMPTYING
00036	6751		LCD			/LOAD THE COMMAND

00037	0000		ZBLOCK	SLP-.		/0000'S WILL EXECUTE AND FALL THROUGH TO SLP!
00040	0000
00041	0000
00042	0000
00043	0000
00044	0000
00045	0000
00046	0000

00047	4053	SLP,	JMS	SLODE		/GET A WORD
00050	3002	SLPSTR,	DCA	SBOOT&177+2	/PUT A WORD
00051	2050		ISZ	SLPSTR		/BUMP TO NEXT WORD
00052	5047		JMP	SLP		/KEEP GOING UNTIL SLP IS OVERLAYED!

00053	5047	SLODE,	.-.			/LOAD A WORD ROUTINE;OK to use same as previous or following or anything else
00054	6753	SLODE1,	STR			/WORD READY?
00055	5033		JMP	SHANGG		/NO, TRY DONE
00056	6752		XDR			/YES, GET A WORD
00057	5453		JMP I	SLODE		/RETURN

00060	7004	SBU,	0^20+7004		/INDICATE UNIT ZERO TO NEXT LEVEL

This is the shortest way to get an RX system going by hand.

cjl