File: VCM200.PG of Tape: Sources/Other/new-22-vista-2
(Source file text)
FILE VCM200 - VISUAL TECHNOLOGY-200
/ TITLE VERSION 01.30 -- COPYRIGHT NOTICE
/
/
/ ******************************************
/ ** **
/ ** V I D E O **
/ ** C H A R A C T E R I S T I C S **
/ ** M O D U L E **
/ ** **
/ ** CODED BY **
/ ** C. E. STEUART DEWAR **
/ ** MARCH, 1980 **
/ ** **
/ ** **
/ ******************************************
/
/
/ COPYRIGHT (c) 1980 Under BERNE and UNIVERSAL COPYRIGHT LAW
/ By: DEWAR INFORMATION SYSTEMS CORPORATION
/
/ The information in this document is subject to change without
/ notice and should not be construed as a commitment by DEWAR
/ INFORMATION SYSTEMS CORPORATION. DEWAR INFORMATION SYSTEMS
/ assumes no responsibility for any errors that may appear in
/ this document other than providing corrections for any such
/ errors when brought to the attention of DEWAR INFORMATION SYS-
/ TEMS CORPORATION.
/
/ The SOFTWARE described in this document is furnished to the
/ purchaser under a license for use on a single computer system
/ and can be copied (with inclusion of DISC's copyright notice)
/ only for use in such system.
/
/ Licensees of the SOFTWARE may make changes to the software
/ with the understanding that the warranty for the SOFTWARE only
/ applies to the original unmodified version delivered to the
/ licensee. The fact that licensee may have modified or changed
/ the SOFTWARE in no way alters or detracts from the copyright
/ protection and proprietary rights due to DISC for the SOFTWARE
/ /01.20
/ REVISION HISTORY /01.20
/ /01.20
/ 1-MAY-80 C.E.S.D MODIFIED TO INCLUDE INSERT BLOCK /01.20
/ REMOVED CURSOR RIGHT FUNCTION /01.21
/ REMOVED CONTROL TAB FUNCTION /01.21
/ 5-MAY-80 C.E.S.D ADDED SMOOTH SCROLL SUPPORT /01.30
/ ADDED VIDEO ENHANCEMENT SUPPORT /01.30
EJECT
/
/ VISTA IS A SCREEN ORIENTED TEXT EDITOR FOR A VISUAL DISPLAY
/ TERMINAL.
/
/ FUNCTION KEYS ON A TERMINAL ARE HANDLED THROUGH THE USE OF
/ THIS VIDEO CHARACTERISTICS MODULE (VCM), THAT HANDLES ALL INPUT TO THE
/ MAIN PORTION OF THE VISTA PROGRAM. IN THE SAME WAY, ALL OUTPUT FROM
/ THE VISTA PROGRAM IS ENCODED AND IT IS THE FUNCTION OF THE /01.20
/ 'VCM' MODULE TO RETRANSLATE THIS OUTPUT INTO A FORM
/ SUITABLE FOR THE SPECIFIC TERMINAL IN USE.
/
/ THE VCM PROVIDED STANDARDLY PROVIDED WITH
/ VISTA HAS BEEN DESIGNED AROUND THE VT52/VT100 TERMINALS SINCE
/ IT IS EXPECTED THAT THESE ARE THE MOST COMMON DISPLAY TERMINALS
/ TO BE FOUND ON PDP8 SYSTEMS.
/
/ IMPLEMENTATION OF OTHER VIDEO DISPLAY TERMINALS IS EXTREMELY
/ SIMPLE SINCE THE MAIN CORE OF THE VISTA PROGRAM IS NEVER
/ CHANGED.
/
/ CONSULT THE 'VISTA' PROGRAM MANUAL FOR DETAILS ON THE USE OF THIS
/ EDITING PROGRAM.
/
/ VIDEO CHARACTERISTICS MODULE IS ALLOCATED 3 PDP8 PAGES FROM
/ 06000-06577
TITLE SCREEN LAYOUT FORMAT
/
/ IN ORDER TO UNDERSTAND HOW VISTA WORKS IT IS ESSENTIAL TO
/ KNOW THE MEMORY LAYOUT.
/
/ A COPY OF EACH LINE ON THE VIDEO SCREEN IS MAINTAINED IN A
/ FIELD 1 BUFFER CALLED 'SCREEN'. EACH BYTE ON THE SCREEN OCCUPIES
/ ONE WORD IN THIS BUFFER.
/
/ A ROW TABLE IS MAINTAINED WHICH CONSISTS OF A ONE WORD ADDRESS
/ FOR EACH LINE ON THE SCREEN. THE ROW TABLE IS SIMPLY A SET OF
/ POINTERS TO THE FIRST WORD ON EACH LINE. THIS FIRST WORD IS
/ A STATUS/COUNT WORD FOR THE LINE WHICH IMMEDIATELY FOLLOWS.
/
/ THE FUNCTION OF THE ROW TABLE IS TO AVOID MOVING THE SCREEN MEMORY
/ AROUND DURING INSERTION AND DELETION OF LINES. IN THIS CASE, ONLY
/ THE ROW TABLE ITSELF HAS TO BE ADJUSTED. FOR THIS REASON, THE
/ POINTER ADDRESSES IN THE ROW TABLE ARE NOT NECESSARY IN ANY ORDER.
/
/ THE FORMAT OF THE STATUS/COUNT WORD FOR EACH LINE IS:
/
/ ABC DEE EEE EEE
/
/ A = 0 CURRENT LINE EXISTS
/ 1 CURRENT LINE DOES NOT EXIST (AT END OF FILE OR UNESTABLISHED)
/
/ B = 0 LINE ENDS WITH CR/LF
/ 1 LINE ENDS WITHOUT CR/LF
/
/ C = 0 LINE NOT MARKED
/ 1 LINE MARKED AS PART OF BLOCK (FOR SAVE/DELETION)
/
/ D = 0 CURRENT LINE HAS NOT BEEN MODIFIED ON THIS EDIT
/ 1 HAS BEEN MODIFIED ON THIS EDIT CYCLE
/
/ EEE..E LINE LENGTH IN THE RANGE 0-255
/
/
/ END OF FILE IS INDICATED BY 'BOF' FLAG BEING SET AND BY ROWS
/ WITH A BIT 0 STATUS OF 1.
/
/ THERE ARE TWO ONE-BLOCK BUFFERS 'FEEDING' THE SCREEN WINDOW:
/ THE ABOVE SCREEN BUFFER (ABUF) AND THE BELOW SCREEN BUFFER
/ (BBUF). THESE BUFFERS ARE IN OS/8 FORMAT AND ARE READ AND
/ WRITTEN FROM THE OS/8 DEVICE AS NEEDED.
/
TITLE IMPORTANT GLOBAL CELLS
/
/ YOU MAY NEED TO BE AWARE OF THE FOLLOWING IMPORTANT CELLS AND
/ ENTRY POINTS IN VISTA:
/
/ NAME FUNCTION
/
/ COL CONTAINS BINARY COLUMN POSITION OF CURSOR IN RANGE
/ 0-(N-1). NOTE: POSITION IS NOT GUARANTEED FOR ALL
/ POSSIBLE VCM FUNCTIONS (BUT IT IS FOR ALL IMPORT/01.20
/ ONES).
/
/ ROW CURRENT POINTER INTO THE ROW TABLE.
/
/ ROWTAB ADDRESS OF FIRST ROW IN ROW TABLE
/ LASTROW ADDRESS OF LAST ROW IN ROW TABLE
/ ROWSIZ COUNT OF NUMBER OF ROWS IN ROW TABLE (1-N)
/ COLSIZ COUNT OF NUMBER OF COLUMNS ON SCREEN
/ PKBD POINTER TO CONSOLE INPUT ROUTINE
/ PSCR POINTER TO CONSOLE OUTPUT ROUTINE
/ XT/XT2 TWO CELLS ON PAGE 0 RESERVED FOR USE BY 'VCM'
/ MODULE. VCM CAN ALLOCATE MORE PAGE 0 STORAGE
/ FROM THE ADDRESS XT2+1 UP TO 177 ON PAGE 0.
/ CAUTION: SPR'S FOR VISTA MAY REQUIRE THE USE OF
/ PAGE 0 CELLS (STARTING BACK FROM 177), SO USE
/ PAGE 0 CELLS ONLY WHEN ABSOLUTELY NECESSARY.
/
/ PRLINE SUBROUTINE TO OUTPUT A FULL ROW ON THE SCREEN.
/ CAN ONLY BE CALLED FROM VCM IF VCM FILE ITSELF
/ PROTECTS AGAINST A RECURSIVE CALL BY SAVING THE
/ RETURN ADDRESSES IN 'PRLINE' AND 'XTER'.
/
/ THIS ROUTINE WILL BE NEEDED FOR TERMINALS THAT ARE
/ CAPABLE OF PERFORMING INSERT AND DELETE LINE IN LOCAL
/ MODE (SEE VCM52 FOR AN EXAMPLE OF CALLING 'PRLINE')
TITLE ASSEMBLY INSTRUCTIONS
/
/ THIS VCM FILE IS TO BE ASSEMBLED WITH THE GLOBAL SYMBOL
/ DICTIONARY FROM VISTA:
/
/ .R PAGE8
/ *VCM,LPT:<VISTA.SD,VCM/I
/
/ OR IF YOU HAVE TO USE PAL8
/
/ .R PAL8
/ *VCM,LPT:<VISTA.EQ,VCM /01.20
/
/ WHERE FOR PAL8, 'VISTA.EQ' IS THE PAGE8 SYMBOL DIRECTORY CONVERT/01.20
/ INTO PAL8 COMPATIBLE FORMAT.
/
XT3 EQU XT2+1 SCRATCH CELL
/
/ ADJUST EQUATE BELOW BASED UPON BAUD RATE. VALUE BELOW IS CORRECT
/ FOR 9600 BAUD.
/
NULCT EQU 142 NUMBER OF NULLS FOR SMOOTH SCROLL TIMING
/
ORG KIO KEYBOARD I/O
DSEC
/
/ ALL FOLLOWING ADDRESSES ARE ABSOLUTELY REFERENCED BY VISTA
/ AND CANNOT BE CHANGED UNLESS VISTA ITSELF IS ALTERED.
/
KIO DC 0 KEYBOARD I/O ENTRY
JMPI PXIN CONTINUE NOW
/
SIO DC 0 SCREEN I/O ENTRY POINT
JMPI PXOUT CONTINUE
/
VMCMNT DC -'/ MINUS ASCII CODE OF COMMENT FIELD CHARACTER
VMTAG DC -', MINUS ASCII CODE OF TAG FIELD DELIMITER
VROWS DC 24 NUMBER OF ROWS ON VIDEO SCREEN
VCOLS DC 80 NUMBER OF COLUMNS ON VIDEO SCREEN
VAUCOL DC 72 STARTING COLUMN FOR AUDIT TRAIL OF VERSION #'S
VSTAT DC 02000 NO XON/XOFF, CTRL/O ALLOWED
/
/ ### END OF FIXED ADDRESS SECTION UTILIZED BY VISTA PROGRAM ###
/
XKIO JMPI KIO HERE TO EXIT FROM 'KIO'
XSIO JMPI SIO HERE TO EXIT FROM 'SIO'
PXIN DC XIN POINTER TO 'XIN'
PXOUT DC XOUT POINTER TO 'XOUT'
TITLE KEYBOARD ESCAPE TRANSLATION TABLE
/
/ VISTA INTERNAL CODE FOR ALL ESCAPED CHARACTERS POSSIBLE ON THE
/ KEYBOARD.
/
/ CHARACTERS PRECEDED BY ESCAPE KEY ONLY
/
PQR DC Y:NEWCMD P ENTER COMMAND MODE
DC Y:TOFC Q TOP OF FILE
DC Y:BOFC R BOTTOM OF FILE
/ /01.11
/ THE FOLLOWING TABLE ENTRIES ARE PRECEDED WITH THE ESCAPE KEY (AND /01.11
/ USUALLY GENERATED MANUALLY) /01.11
/ /01.11
ESCDIG DC Y:INSBLK 1 INSERT BLOCK /01.11
DC Y:DELSCR 2 DELETE SCREEN /01.11
DC Y:TRUNCF 3 TRUNCATE FILE /01.11
/
/ CHARACTERS PRECEDED BY ESCAPE KEY ONLY
/
SPST DC Y:PAGEUP SP PAGE UP
DC Y:PAGEDN ! PAGE DOWN
DC Y:UNMKROW " UNMARK LINE
DC Y:MKROW # MARK LINE
DC Y:PICKUP $ PICKUP
DC Y:PUTDN % PUT DOWN
DC Y:RSTEP & REPLACEMENT STEP
DC Y:RCONT ' REPLACEMENT CONTINUOUS
DC Y:DISMOD ( DISPLAY MODIFIED LINES
DC Y:DOSCRN ) RESTORE SCREEN
DC Y:ROWINS * INSERT ROW
/
/ LOWER CASE CHARACTERS PRECEDED BY ESCAPE AND QUESTION MARK
/
LMN DC Y:CDOWN L CURSOR DOWN
DC Y:AWAY M CURSOR TO AWAY POSITION
DC Y:WRIGHT N WORD RIGHT
DC 0 O
DC Y:WLEFT P WORD LEFT
DC Y:CLEFT Q CURSOR LEFT
DC Y:HOME R HOME CURSOR
DC Y:CRIGHT S CURSOR RIGHT
DC Y:CEOL T CURSOR TO END OF LINE
DC Y:CUP U CURSOR UP
DC Y:SCRLDN V SCROLL DOWN
DC Y:CNEXTL W CURSOR TO START OF NEXT LINE
DC Y:SEARCH X SEARCH KEY
DC Y:SCRLUP Y SCROLL UP
/
/ ASCII CONTROL CODE TABLE
/
ITRAN DC 0 CTRL/NULL
DC Y:TRANSP CTRL/A TRANSPARENT MODE
DC Y:DISMOD CTRL/B DISPLAY MODIFIED LINES
DC Y:QUIT CTRL/C ABORT TO OS/8
DC Y:CSTART CTRL/D CURSOR TO START OF LINE
DC Y:TABL CTRL/E TAB LEFT
DC Y:CEOL CTRL/F CURSOR TO END OF CURRENT LINE
DC Y:UNMKROW CTRL/G UNMARK ROW
DC Y:BKDEL CTRL/H BACKSPACE DELETE
DC Y:TABR CTRL/I TAB RIGHT
DC Y:INSTOG CTRL/J INSERT CHARACTER TOGGLE
DC Y:DELWD CTRL/K DELETE WORD
DC Y:DELEWD CTRL/L DELETE TO END OF WORD
DC Y:RETURN CTRL/M RETURN CODE
DC Y:DOSCRN CTRL/N RESTORE SCREEN
DC 0 CTRL/O
DC Y:CASE CTRL/P INVERT CASE OF WORD
DC 0 CTRL/Q
DC Y:RCONT CTRL/R CONTINUOUS REPLACE
DC 0 CTRL/S
DC Y:RSTEP CTRL/T
DC Y:DLETLN CTRL/U DELETE LINE
DC 0 CTRL/V
DC Y:AWAY CTRL/W CURSOR TO AWAY POSITION
DC 0 CTRL/X
DC Y:CNEXTL CTRL/Y CURSOR TO START OF NEXT LINE
DC Y:XEDIT CTRL/Z CLOSE FILE
DC 0 CTRL/[
DC 0 CTRL/\
DC 0 CTRL/]
DC Y:INSBLK CTRL/^ INSERT BLOCK /01.20
DC Y:TRUNCF CTRL/_ TRUNCATE FILE
TITLE SCREEN TRANSLATION TABLE
/
/ DISPATCH TABLE FOR OUTPUT FUNCTION CODES
/
XTAB DC Z:POS 0 POSITION CURSOR
DC Z:INIT 1 INITIALIZE SCREEN
DC Z:SPAC 2 TABULATION/PAD CODE /01.21
DC Z:CRLF 3 CR/LF TYPE SEQUENCE
DC Z:EOL 4 ERASE TO END OF LINE
DC Z:CLSC 5 CLEAR SCREEN AND HOME CURSOR
DC Z:INS 6 INSERT LINE
DC Z:DEL 7 DELETE LINE
DC Z:BEL 8 RING BELL
DC Z:BKSP 9 BACKSPACE
DC Z:SPV1 10 SPECIAL VIDEO MODE 1
DC Z:SPV2 11 SPECIAL VIDEO MODE 2
DC Z:NMV 12 NORMAL VIDEO MODE
DC Z:END 13 NO-CRLF AT END OF LINE GRAPHIC /01.21
DC Z:RTN 14 RETURN TERMINAL TO ORIGINAL CONDITION/01.21
DC Z:CTRL 15 CONTROL CODE-NON-DISPLAYABLE /01.21
TITLE TRANSLATION ROUTINES
/
ISEC 0
/
/ ENTER HERE TO GET NEXT CHARACTER FROM CONSOLE TERMINAL.
/ ALL CHARACTERS ARE RETURNED IMMEDIATELY AND DIRECTLY
/ EXCEPT FOR THE ESCAPE/CONTROL CODES WHICH ARE USED TO IMPLEMENT
/ ALL FUNCTIONS.
/
XIN JMSI PKBD GET CHARACTER FROM KEYBOARD
TAD =-0233 TEST FOR ESCAPE CODE
SNA SKIP IF NOT
JMP 1F HANDLE ESCAPE CODE
TAD =0233-0240 TEST FOR CONTROL CODE
SPA SKIP IF NOT CONTROL CODE
JMP 0F ELSE HANDLE CONTROL CODE
TAD =0240 RESTORE NORMAL CHARACTER
JMP XKIO RETURN DIRECTLY TO VISTA
/
/ HERE ON CONTROL CODE.
/
0H TAD =ITRAN+040 BIAS CODE TO RANGE 0-37
JMP 2F MERGE BELOW TO GET ASSOCIATED CODE
/
/ HERE ON ESCAPE CODE.
/ NEXT CHARACTER MUST BE:
/ QUESTION MARK = 3 CHAR SEQUENCE
/ P-R FIRST 3 FUNCTION KEYS
/ SPACE-* NEXT 11 FUNCTION KEYS
/
1H JMSI PKBD READ CHARACTER AFTER ESCAPE CODE
TAD =-'? 3-CHAR ESCAPE SEQUENCE?
SNA SKIP IF NOT
JMP THRCHR HANDLE THREE CHARACTER SEQUENCE
/ /01.11
/ CHECK FOR 1-3 FOR ESCAPE/DIGIT TYPE SEQUENCES /01.11
/ /01.11
TAD ='?-'3-1 TEST FOR 1-3 /01.11
CLL ... /01.11
TAD ='3-'1+1 ... /01.11
SZL DIGIT 1-3 HERE? /01.11
JMP DO123 YES: HANDLE THIS /01.11
/
/ HERE TO CHECK FOR P-R
/
ADCK TAD ='1-'R-1 TEST FOR P-R
CLL ...
TAD ='R-'P+1 ...
SZL SKIP IF NOT P-R
JMP DOPQR ELSE HANDLE A-D HERE
TAD ='P-'*-1 SPACE THROUGH STAR?
CLL ...
TAD ='*-' +1 ...
SZL
JMP DOSPST SPACE-STAR
JMP BADESC ELSE HANDLE BAD ESCAPE SEQUENCE NOW
/
THRCHR JMSI PKBD READ THIRD CHARACTER OF SEQUENCE
TAD =-('Y+040)-1 L-Y LOWER CASE?
CLL ...
TAD ='Y-'L+1 ...
SZL
JMP DOLMN L-Y LOWER CASE
BADESC CLA
JMP XIN SOMETHING ELSE: IGNORE IT
/
DO123 TAD =ESCDIG-PQR INDEX TABLE
DOPQR TAD =PQR-SPST ...
DOSPST TAD =SPST-LMN ...
DOLMN TAD =LMN ...
/
2H DCA XT ...
CDF %*
TADI XT LOAD VISTA INTERNAL CODE
CDF BUF RESET TO MAIN BUFFER FIELD
SZA IS THIS AN UNDEFINED CODE?
JMP XKIO NO: SO RETURN IT IN THE AC
JMP XIN YES: SO STRIP COMPLETELY
TITLE VCM OUTPUT SECTION
/
/ ENTER HERE WITH CHARACTER TO BE OUTPUT TO THE SCREEN
/
XOUT DCA XT SAVE CHARACTER FOR A MOMENT
TAD XT REGET CHARACTER
TAD =-0200 LOWEST ASCII CODE
SPA SKIP IF DISPLAYABLE CODE
JMP 1F ELSE OFF FOR FUNCTION CODE
TAD =0200 NORMAL CODE: RESTORE IT
CHOUT JMSI PSCR OUTPUT BACK TO SCREEN
/
/ COME HERE TO IGNORE CHARACTER
/
XNULL JMP XSIO ALL DONE HERE
/
/ HERE FOR VIDEO MODES. USE HALF INTENSITY FEATURE FOR MARKED LINE/01.30
/ /01.30
Z:NMV LDI -1 NORMAL VIDEO: FULL INTENSITY /01.30
/
Z:SPV1 TAD ='4 SPECIAL VIDEO: HALF INTENSITY /01.30
Z:SPV2 QUT %*,Z:SPV1 ... /01.30
JMP ESCX SEND ESCAPE SEQUENCE /01.30
/
/ HERE ON END OF LINE CODE- MUST DISPLAY SOME KIND OF GRAPHIC
/ ON SCREEN.
/
Z:END TAD ='A-'P GRAPHIC FOR END OF LINE
Z:CTRL TAD ='P+040 GRAPHIC FOR CONTROL CHARACTER
DCA XT2 SAVE FOR A MOMENT
TAD ='F ENTER GRAPHICS MODE
JMS DOESC ...
TAD XT2 GENERATES NICE GRAPHIC
JMSI PSCR ...
RESETG TAD ='G RE-SET GRAPHICS MODE
JMP ESCX ALL DONE HERE
/
/ HERE ON INITIAL ENTRY, MUST ENSURE GRAPHICS MODE CLEAR AND ALSO SET
/ ALTERNATE KEYPAD MODE
/
Z:RTN TAD ='>-'= RESET ALTERNATE KEYPAD MODE FOR EXIT
Z:IN IT TAD ='= ESCAPE/= SETS ALTERNATE KEYPAD MODE
JMS DOESC ...
JMP RESETG END UP NOW BY RESETTING GRAPHICS MODE
/
/ HERE ON FUNCTION CODE: INDEX DISPATCH TABLE
/
1H TAD =XTAB+0200 INDEX DISPATCH TABLE
DCA XT2 ...
CDF %* TO CURRENT FIELD
TADI XT2 GET ADDRESS
CDF BUF BACK TO BUFFER FIELD
DCA XT2 ...
JMPI XT2 PASS CONTROL NOW
/
/ HERE ON CONTROL CODE WHICH WE WISH TO SEND NORMALLY
/
OCTRL TAD XT REGET THE CONTROL CHARACTER
JMP CHOUT OUTPUT CHARACTER NOW
EJECT
/
/ HERE FOR BACKSPACE/BELL/TAB AND PAD FUNCTIONS
/
Z:BEL LDI -1 CONTROL/G DOES BELL FUNCTION
Z:BKSP TAD =0210-' CONTROL/H DOES BACKSPACE FUNCTION
Z:SPAC TAD =' TAB/PAD CODE BECOMES A SPACE CODE
JMP CHOUT ...
/
/ HERE FOR SIMPLE TWO-CHARACTER ESCAPE FUNCTIONS
/
Z:EOL TAD ='K-'C DO ESCAPE/K FOR ERASE TO EOL
Z:CRI TAD ='C ESCAPE/C IS CURSOR RIGHT
ESCX JMS DOESC DO ESCAPE SEQUENCE
JMP XSIO ALL DONE HERE
/
/ HERE FOR DELETE LINE. IF DELETING TOP LINE ON SCREEN, CURSOR POSITION
/ TO BOTTOM LINE AND ISSUE LINE FEED. IT HAS THE SAME EFFECT AND HAS THE
/ ADVANTAGE ON THE VISUAL-200 OF ENABLING THE SMOOTH SCROLL. THE
/ SMOOTH SCROLL IS NOT PERFECT BECAUSE OF DISC/TAPE I/O, BUT IT'S CLOSE
/
Z:DEL TAD ROW GET CURRENT ROW POSITION
CMA IAC SUBTRACT FROM
TAD ROWTAB FIRST ROW IN ROW TABLE
SZA CLA SKIP IF DELETING TOP ROW
JMP Z:DEL2 NOT TOP ROW: JUST DO DELETE LINE THEN
/
/ HERE FOR DELETE OF TOP ROW. ISSUE LINE FEED ON BOTTOM ROW.
/
LDI -1 COMPUTE BINARY POSITION OF LAST ROW
TAD ROWSIZ ...
JMS MOVEC MOVE CURSOR TO THAT ROW
/
/ GET LENGTH OF CURRENT BOTTOM LINE ON SCREEN TO CALCULATE HOW
/ MANY NULLS TO SEND OUT.
/
LDI -1 LAST ROW IS NOW ON 2ND TO LAST ROW
TAD LASTROW ...
DCA XT SAVE POINTER TO 2ND TO LAST ROW
TADI XT GET ADDRESS OF LENGTH/STATUS
DCA XT SET POINTER
TADI XT GET THE LENGTH/STATUS WORD
AND =0377 ISOLATE THE LENGTH FIELD
TAD =-NULCT NUMBER OF NULLS NEEDED AT BAUD RATE
JMS NULSUB GENERATE THAT NUMBER OF NULLS NOW
TAD =LF ISSUE LINE FEED ON THAT ROW
JMSI PSCR ...
JMS MOVEC MOVE CURSOR BACK TO TOP ROW
JMP DONULLS FOR SAFETY, FOLLOW WITH NULL STRING
/
/ DELETE LINE, INSERT LINE AND CLEAR SCREEN.
/
Z:DEL2 TAD ='M-('V+040) ESCAPE/M DELETES LINE
Z:CLSC TAD ='V+040-'L DO ESCAPE/v FOR CLEAR SCREEN
Z:INS TAD ='L ESCAPE/L INSERTS LINE
JMS DOESC ...
/
/ COME HERE TO ISSUE A ST RING OF NULLS TO AVOID TIMING PROBLEMS
/
DONULLS TAD =-30 FOLLOW WITH 30 NULLS FOR TIMING
JMS NULSUB CALL NULL SUBROUTINE
JMP XSIO ALL DONE HERE
/
/ SUBROUTINE TO GENERATE NULLS. CALL WITH NEGATIVE NUMBER OF NULLS
/ TO GENERATE IN AC ON ENTRY.
/
NULSUB SUB
DCA XT ...
2H TAD =NULL OUTPUT NULLS
JMSI PSCR ...
ISZ XT MORE NULLS?
JMP 2B YES: DO THEM
RET NULSUB NO: ALL DONE HERE
/
/ OUTPUT ESCAPE SEQUENCE, CHAR IN AC
/
DOESC SUB
DCA XT SAVE CHARACTER
TAD =0233 OUTPUT ESCAPE CODE
JMSI PSCR ...
TAD XT REGET CHARACTER
JMSI PSCR ...
RET DOESC ALL DONE HERE
/
/ HERE FOR CR/LF ON SCREEN.
/
Z:CRLF TAD =CR CARRIAGE RETURN
JMSI PSCR ...
TAD =LF LINE FEED
JMP CHOUT ...
EJECT
/
/ HERE FOR POSITION CURSOR COMMAND. IN THIS CASE, WE POSITION
/ TO THE ROW AND COLUMN SPECIFIED BY 'ROW' AND 'COL'
/
/ VISUAL-200 REQUIRES:
/
/ ESC Y L C
/
/ WHERE X IS THE LINE NUMBER, AND Y IS THE COLUMN POSITION
/
Z:POS TAD ROWTAB START OF ROW TABLE
CMA IAC NEGATE AND SUBTRACT FROM
TAD ROW CURRENT ROW POSITION
JMS MOVEC MOVE CURSOR TO THAT ROW NOW
JMP XSIO ALL DONE HERE
/
/ SUBROUTINE TO MOVE TO A PARTICULAR ROW AND COLUMN. ON ENTRY
/ 'COL' HAS THE DESIRED COLUMN, AND THE AC HAS THE BINARY ROW
/ POSITION THAT WE WANT.
/
MOVEC SUB
TAD =' BUILD ASCII CODE FOR LINE POSITION
DCA XT3 SAVE FOR A MOMENT
TAD ='Y START OF POSITIONING SEQUENCE
JMS DOESC START THE SEQUENCE
TAD XT3 GET ROW POSITION
JMSI PSCR OUTPUT THAT
TAD COL GET THE BINARY COLUMN POSITION
TAD =' BUILD ASCII CODE FOR COLUMN
JMSI PSCR OUTPUT THAT
RET MOVEC ALL DONE HERE