ddtord.6

INTRODUCTION

 THE SITS DDT IS A PROGRAM USED TO DEBUG OTHER PROGRAMS.
IT BEHAVES MUCH LIKE THE DDT ON THE ITS SYSTEM. TO USE DDT, ONE
LOADS AN ASSEMBLY LANGUAGE PROGRAM STORED AS A FILE IN A SPECIAL
FORMAT AS AN "INFERIOR" TO DDT.  ONLY FILES IN ONE OF THE SPECIAL
FORMATS CAN BE LOADED; FILES IN OTHER FORMATS WILL CAUSE AN ERROR.
ONCE LOADED, THE PROGRAM CAN BE RUN IN A CONTROLLED FASHION, STOPPED,
AND LOCATIONS IN THE PROGRAM EXAMINED AND CHANGED.
     COMMANDS TO DDT COME IN SEVERAL DIFFERENT VARIETIES. PERHAPS
THE SIMPLEST ARE THE COLON COMMANDS, EXECUTED BY TYPING A COLON
FOLLOWED BY THE NAME OF THE COMMAND AND PERHAPS SOME ARGUMENTS
DEPENDING UPON THE COMMAND, AND TERMINATED BY A CARRIAGE RETURN.
MANY OF THE COLON COMMANDS HAVE
ABBREVIATED FORMS AND CAN BE EXECUTED BY SIMPLY TYPING SOME
CONTROL CHARACTER OR AN ALTMODE (ECHOS AS $) AND ANOTHER CHAR.



DDT FILE NAME CONVENTIONS

 SITS DDT DIFFERS FROM ITS IN THE
WAY FILE NAMES ARE INTERPRETED, BECAUSE SITS HAS A GENERALIZED
TREE STRUCTURE FILE SYSTEM. AT ANY TIME, THE USER HAS A DEFAULT
DIRECTORY WHICH CAN BE LISTED BY TYPING :LISTF. THE FILE
NAME THE USER TYPES IS INTERPRETED AS BEING RELATIVE TO EITHER
HIS DEFAULT DIRECTORY OR TO THE ROOT OF THE FILE SYSTEM. A
FILE NAME CONTAINING ONE OF THE ROOTS SUCH AS 0; 1; OR 2; IS
INTERPRETED AS BEING RELATIVE TO THAT ROOT. THE SEMICOLON IS
THE KEY CHARACTER.  A FILE NAME WITHOUT THE SEMICOLON WILL BE
ASSUMED TO BE RELATIVE TO THE DEFAULT DIRECTORY, THAT IS, THE
FIRST NAME TYPED SHOULD BE A FILE OR DIRECTORY IN THE DEFAULT
DIRECTORY, THE NEXT NAME WILL BE A FILE OR DIRECTORY IN THAT
DIRECTORY AND SO ON UNTIL THERE ARE NO MORE NAMES IN THE FILE
NAME STRING. EXAMPLES:

:LISTF			LISTS THE USER'S DEFAULT DIRECTORY.
:LISTF 1; USERS EPG	LIST'S EPG'S DIRECTORY IN USERS, DISK 1.

:PRINT FOO		PRINTS THE FILE FOO IN THE USER'S DEFAULT DIRECTORY.
:LOAD 0; . INQUIR	LOADS THE PROGRAM INQUIR IN THE . DIRECTORY
			FROM DISK 0.

COLON COMMANDS

   THE COLON COMMANDS MAY SPECIFY A DDT COMMAND, OR IF THERE
IS NO DDT COMMAND BY THAT NAME, DDT WILL TRY TO RUN A PROGRAM
WITH THAT NAME LOADING FROM THE USER'S DEFAULT DIRECTORY. THE
FILE MUST BE IN A LOADER FORMAT.  THE FILE IS LOADED WITHOUT
THE SYMBOLS AND IS STARTED IMMEDIATELY AS IF THE USER HAD TYPED
$G.  IF THE SYMBOLS ARE DESIRED WHEN THE PROGRAM RETURNS TO DDT,
THEY CAN BE LOADED VIA :SYMADD.

:BINLOAD  (FILE NAME) 	LOADS A FILE IN ANY FORMAT WITHOUT
			INTERPRETING THE FORMAT INTO AN INFERIOR
			SPHERE. THE PROGRAM CANNOT BE STARTED
			VIA $G. USEFUL FOR SEEING EXACTLY WHAT
			IS IN A FILE.

:CAPMODE		CAUSES DDT TO OPEN THE INFERIOR SPHERE'S
			CAPABILITIES INSTEAD OF MEMORY. THUS:
			3/  $S   PRINTS THE TYPE OF CAPABILITY 3.
			TO GO BACK TO LOOKING AT MEMORY, USE :ISPACE.

:DELETE (FILENAME)	DELETES THAT FILE.

:DSPACE			CAUSES LOCATIONS TO BE OPENED FROM MEMORY
			IN D SPACE.

:DUMP (FILENAME)	CREATES A FILE WITH THE GIVEN FILE NAME
			AND DUMPS THE CURRENT INFERIOR SPHERE
			IN ABSOLUTE LOADER FORMAT.

:FONT (N)		CHANGES THE CURRENT FONT OF THIS TTY TO
			FONT N. NOT ESPECIALLY USEFUL ON PRINTING
			TERMINALS.

:ISPACE			CAUSES LOCATIONS TO BE OPENED FROM MEMORY
			IN I SPACE. (USUALLY THE SAME AS D SPACE).

:LISTF (DIR NAME)	LISTS THE CONTENTS OF THE SPECIFIED DIRECTORY.

:LOAD (FILENAME)	LOADS THE SPECIFIED FILE INTO AN INFERIOR
			SPHERE. FILE MUST BE IN EITHER ABSOLUTE
			LOADER FORMAT OR PURE LOAD FORMAT.

:LOGOUT			RETURNS TO DDT'S SUPERIOR "SUCCESSFULLY".
			IF THE SUPERIOR IS SYSSPR, THE USER WILL 
			BE LOGGED OUT OF THE SYSTEM.

:MAPMODE		CAUSES LOCATIONS TO BE INTERPRETED AS
			PAGE DESCRIPTORS IN THE SAME FASHION
			AS CAPMODE. USE :ISPACE TO UNDO.

:NEWSPH			CREATES A NEW INFERIOR SPHERE WITHOUT
			LOADING ANY FILE INTO IT. A PROGRAM
			CAN BE WRITTEN AND RUN IN THIS FASHION
			ALTHOUGH USING ASSEMBLER IS EASIER.

:PDUMP (FILENAME)	CREATES A FILE AND DUMPS THE CURRENT
			INFERIOR SPHERE IN PURE FORMAT.

:PRINT (FILENAME)	PRINTS THE CONTENTS OF FILE ON THE TTY.
			TYPING CONTROL S CAUSES IT TO SHUT UP
			EVENTUALLY.

:REVERSE		CAUSES BLACK TO BECOME WHITE AND WHITE
			TO BECOME BLACK (GREEN?) ON TVS.

:SETD (DIR NAME)	CAUSES DIR NAME TO BECOME THE DEFAULT
			DIRECTORY. NOTE THAT DIR NAME IS INTER-
			PRETTED JUST LIKE A FILE NAME, SO THAT
			IF NO ROOT IS SPECIFIED, THE NEW DIRECTORY
			WILL BE INFERIOR TO THE OLD ONE.

:SSTAT			PRINTS THE VERSION NUMBER OF SITS AND
			DDT AND A RANDOM NUMBER INTENDED TO BE
			LENGTH OF TIME THE SYSTEM HAS BEEN UP.

:SYMADD (FILENAME)	LOADS JUST THE SYMBOLS FROM A PURE OR
			ABSOLUTE FORMAT FILE.


:?			PRINTS A LIST OF COLON COMMANDS.



CONTROL COMMANDS

^A	APPEND THE SYMBOLS OF THIS FILE TO SYMBOL TABLE. FILE SYNTAX
^B	ERROR
^C	CREATE A NEW SPHERE AND PROCESS, BUT DO NOT LOAD PROGRAM
^D	FLUSH THIS COMMAND AND GET A NEW ONE. ALSO END SEARCHES ETC.
^E	ERROR
^F	PRINT A DIRECTORY. FILE SYNTAX.
^G	ERROR
^H	ERROR
^I(TAB)	OPEN THE LAST ADDRESS MENTIONED.
^J(LINEFEED) OPEN THE NEXT LOCATION. (.+ LINEFEED INCREMENT)
^K	ERROR
^L	COPY A FILE INTO A SPHERE PAGE BY PAGE (UP TO 8 PAGES)
^M(CR)	CLOSE ANY OPEN LOCATION.
^N	SINGLE STEP. ARG^N STEPS ARG INSTRUCTIONS.
^O	DELETE FILE. FILE SYNTAX.
^P	PROCEDE LIKE $$P BUT DON'T PRINT AT BREAKPOINTS.
^Q	PROCEDE LIKE $P.
^R	PRINT A FILE. TYPEOUT CAN BE HALTED BY ^S.
^S	FLUSH ANY TYPEOUT GENERATED BY THE PREVIOUS COMMAND.
^T	ERROR
^U	ERROR
^V	ERROR
^W	ERROR
^X	SINGLE STEP. (SAME AS ^N).
^Y	ERROR
^Z	BREAK, THAT IS, RETURN TO DDT'S SUPERIOR VIA BREAKPOINT.




DDT ENTRY TYPES

$nB	PROCESS HIT THE nTH BREAKPOINT
SS	THE PREVIOUS INSTRUCTION WAS SINGLE STEPPED
BPT	PROCESS EXECUTED A RANDOM BPT INSTRUCTION
IOT	PROCESS EXECUTED AN IOT
TRP	PROCESS EXECUTED A TRAP INSTRUCTION
EMT	PROCESS EXECUTED A BAD EMT
ILL	PROCESS EXECUTED AN ILLEGAL INSTRUCTION
FPP	FLOATING POINT EXCEPTION
BET	BUSS ERROR
SLE	SEGMENT LENGTH ERROR
RDO	READ ONLY VIOLATION
NXM	NON EXISTANT MEMORY VIOLATION
UNK	FAULT TYPE IS NOT KNOW BY DDT


MISCELLANEOUS COMMANDS

:	DEFINE A SYMBOL. ARG<SYMB: DEFINES SYMB WITH VALUE ARG. DEFAULT ARG IS .
^	OPEN PREVIOUS WORD (.-2)
_	OPEN PREVIOUS LAST ADDRESS. FOO/ MOV A,B  _ OPENS A.
[	OPEN LIKE SLASH IN WORD MODE.
@	OPEN CONTENTS OF PC



PERMANENT SYMBOLS IN DDT

%0-%7	REGISTERS OF THE CURRENT PROCESS
%PS	PROGRAM STATUS REGISTER
%AC0-%AC6  FLOATING POINT REGISTERS
%FPS	FLOATING POINTS STATUS REGISTER
%SADDR	STARTING ADDRESS (WHERE YOU GO ON $G)
%PFAUL	FAULT WORD OF THE PROCESS
%PERRW	ERROR WORD OF THE PROCESS
%TARGE	TARGET WORD FOR SEARCHES
%USRBE	BEGINNING OF USER MEMORY (USED AS DEFAULT ON SEARCHES)
%USREN	END OF USER MEMORY (ALSO DEFAULT FOR SEARCHES)
%MXOFF	MAXIMUM OFFSET FOR RELATIVE ADDRESS TYPEOUT



ALTMODE COMMANDS

$^A	ERROR
$$^A	ERROR
$^B	TEMPORARY BYTE MODE. TYPE VALUES AS UNSIGNED INTEGERS. SET LFINC TO 1.
$$^B	PERMANENT BYTE MODE
$^C	TEMPORARY CAPABILITY MODE. ARG/ RETURNS VALUE OF USERS CAP NO.ARG
$$^C	PERMANENT CAPABILITY MODE.
$^D	ERROR
$$^D	ERROR
$^E	ERROR
$$^E	ERROR
$^F	ERROR
$$^F	ERROR
$^G	ERROR
$$^G	ERROR
$^H	ERROR
$$^H	ERROR
$^I	TEMPORARY I SPACE MODE. OPEN LOCATIONS FROM I SPACE.
$$^I	PERMANENT I SPACE MODE.
$^J	ERROR
$$^J	ERROR
$^K	ERROR
$$^K	ERROR
$^M	ERROR
$$^M	ERROR
$^N	ERROR
$$^N	ERROR
$^O	ERROR
$$^O	ERROR
$^P	DOUBLE PRECISON FLOATING MODE. FLOAT VALUES ARE DOUBLE PRECISION
$$^P	SINGLE PRECISION FLOATING MODE.
$^Q	ERROR
$$^Q	ERROR
$^R	ERROR
$$^R	ERROR
$^S	ERROR
$$^S	ERROR
$^T	ERROR
$$^T	ERROR
$^U	TEMPORARY UPT OR PAGE MAP MODE. ARG/ = VALUE OF MAP WORD ARG
$$^U	PERMANENT UPT MODE
$^V	ERROR
$$^V	ERROR
$^W	TEMPORARY D SPACE MODE. OPEN LOCATIONS FROM D SPACE.
$$^W	PERMANENT D SPACE MODE.
$^X	ERROR
$$^X	ERROR
$^Y	ERROR
$$^Y	ERROR
$^Z	ERROR
$$^Z	ERROR

$A	TEMPORARY ABSOLUTE MODE. ADDRESSESS TYPED AS UNSIGNED INTEGERS.
$$A	PERMANENT ABSOLUTE MODE.
$B	SET A BREAKPOINT. ARG$B SETS A BREAKPOINT AT LOCATION ARG.
$$B	FLUSH ALL BREAKPOINTS. ARG$$B FLUSHES ONLY THE ONE AT ARG.
$C	TEMPORARY CONSTANTS MODE. LOCATIONS TYPED AS UNSIGNED INTEGERS.
$$C	PERMANENT CONSTANTS MODE.
$D	TEMPORARY DECIMAL MODE. SETS CURRENT RADIX TO 10.
$$D	PERMANENT DECIMAL MODE.
$E	EFFECTIVE ADDRESS SEARCH.
$$E	EFFECTIVE ADDRESS SEARCH.
$F	TEMPORARY FLOAT MODE. TYPE VALUES AS FLOATING NUMBERS.
$$F	PERMANENT FLOAT MODE.
$G	GO. ARG$G START PROCESS AT ARG. $G STARTS AT %SADDR.
$$G	GO. ARG$$G STARTS PROCESS LIKE ARG$G THEN SETS %SADDR TO ARG.
$H	TEMPORARY HALFWORD MODE. VALUE TYPED AS HIGHBYTE,,LOWBYTE
$$H	PERMANENT HALFWORD MODE.
$I	TEMPORARY INSTRUCTION MODE. VALUE TYPED AS INSTRUCTIONS.
$$I	PERMANENT INSTRUCTION MODE.
$J	ERROR
$$J	ERROR
$K	HALF KILL SYMBOL. SYMB$K HALF KILLS SYMB.
$$K	KILL SYMBOL. SYMB$$K KILLS SYMB. $$K KILLS ALL SYMBOLS.
$L	LOAD FILE. CREATES SPHERE AND PROCESS. FILE SYNTAX.
$$L	USE NEW VERSION OF LOADER WHICH ALSO READS PLOAD FILES
$M	VALUE OF %MASK.
$$M	VALUE OF %MASK.
$N	NOT WORD SEARCH.
$$N	NOT WORD SEARCH.
$O	TEMPORARY OCTAL MODE. TYPES NUMBERS IN OCTAL RADIX.
$$O	PERMANENT OCTAL MODE.
$P	PROCEDE FROM A BREAKPOINT.
$$P	PROCEDE AND PASS THROUGH BREAKS UNTIL ^D TYPED.
$Q	VALUE OF LAST QUANTITY MENTIONED.
$$Q	VALUE OF LAST QUANTITY MENTIONED.
$R	TEMPORARY RELATIVE MODE. ADDRESSES TYPED RELATIVE TO SYMBOLS.
$$R	PERMANENT RELATIVE MODE.
$S	TEMPORARY SYMBOLIC MODE. VALUES TYPED AS SYMBOLS.
$$S	PERMANENT SYMBOLIC MODE.
$T	TEMPORARY TEXT MODE. VALUES TYPED AS TEXT. ASCII DEFAULT
$$T	PERMANENT TEXT MODE. NOTE: $5T = RADIX 50, $7T = ASCII
$U	ERROR
$$U	ERROR
$V	ENABLE FLOATING POINT INSTRUCTION TYPEOUT.
$$V	DISABLE FLOATING POINT INSTRUCTION TYPEOUT.
$W	WORD SEARCH.
$$W	WORD SEARCH.
$X	EXECUTE. INST$X EXECUTES THE INSTRUCTION INST IN PROCESS AND SPHERE.
$$X	EXECUTE.
$Y	YANK FILE. (WRITE MEMORY INTO FILE). FILE SYNTAX. ABSOLUTE FORMAT
$$Y	YANK FILE. PURE FORMAT
$Z	ZERO MEMORY BETWEEN BOUNDS.
$$Z	ZERO ALL OF MEMORY.