ASMB,R,Q,C
      HED <<RTE BASIC - SYNTAX/SEG #1>>       92101-16003 REV.2040
      NAM BASC1,5 92101-16003 REV.2040 800803 
* 
* 
* 
**************************************************************
* (C) COPYRIGHT HEWLETT-PACKARD COMPANY 1975.  ALL RIGHTS    *
* RESERVED.  NO PART OF THIS PROGRAM MAY BE PHOTOCOPIED, RE- *
* PRODUCED, OR TRANSLATED TO ANOTHER PROGRAM LANGUAGE WITH-  *
* OUT THE PRIOR WRITTEN CONSENT OF HEWLETT-PACKARD COMPANY.  *
**************************************************************
* 
* 
* 
*      NAME:      BASC1 
*      SOURCE:    92101-18003 
*      RELOC:     92101-16003 
*      PGMR:      B.J.L.
* 
* 
* 
************************************************************* 
* 
* 
      ENT BASC1 
      EXT PLIST,PEXMK,GETCR,LETCK,DIGCK,INTCK,MVTOH 
      EXT BCKSP,FNDPS,NUMCK,OUTER 
      EXT FCNS,FCNCT,SPEC1,SPTBL,SPNCT
      EXT GMS.C,ROTAT 
      COM TEMPS(32),PNTRS(75),FILBF(16),FLDCB(144),SPEC(10) 
* 
* INCREASED PNTRS TO 75 *2040*800803* 
* 
* INCREASED TEMPS TO 32 *800130*BL* 
* 
****************************************************
*                                                  *
*    SEGMENT #1: CHECK SYNTAX AND TRANSLITERATE    *
*                                                  *
****************************************************
* 
*  THIS PART OF THE INTERPRETER IS LOADED BY THE BASIC MAIN CONTROL 
*    WHENEVER A RECORD IS INPUT WITH A NUMBER AS THE FIRST CHAR. IT 
*    WILL CONVERT AN ASCII STATEMENT RECORD INTO THE SPECIAL BINARY 
*    CODE WHICH IS USED BY THE LIST AND EXECUTION SEGMENTS OF THE 
*    INTERPRETER. AFTER EACH STATEMENT IS PROCESSED, EXECUTION IS 
*    RETURNED TO THE MAIN CONTROL PROGRAM. THE GENERAL FORM OF THE
*    TRANSLITERATED CODE IS SHOWN BELOW:
* 
*       WORD #1 - LINE NUMBER 
*       WORD #2 - # WORDS IN TRANSLITERATED STATEMENT 
*       WORD #3 > WORD #N - OPERATORS, CONSTANTS, ETC.
      SKP 
*************************** 
*                         * 
* CONSTANTS AND VARIABLES * 
*                         * 
*************************** 
* 
FWAM  EQU PNTRS     FIRST WORD OF AVAILABLE MEMORY
LWBM  EQU PNTRS+1   LAST WORD OF AVAILABLE MEMORY 
.INBF EQU PNTRS+2   INPUT BUFFER ADDRESS
SBUFA EQU PNTRS+3   SYNTAX BUFFER ADDRESS 
SYMTA EQU PNTRS+4   START OF SYMBOL TABLE 
SYMTF EQU PNTRS+5   END OF SYMBOL TABLE 
PBUFF EQU PNTRS+6   FIRST WORD OF USER PROGRAM
PBPTR EQU PNTRS+7   LAST WORD+1 OF USER PROGRAM 
INBFA EQU PNTRS+8   INPUT BUFFER POINTER
ICCNT EQU PNTRS+9   INPUT CHARACTER COUNT 
SBPTR EQU PNTRS+10  SYNTAX BUFFER POINTER 
.LNUM EQU PNTRS+11  CURRENT LINE #
FCORE EQU PNTRS+12  START OF FREE CORE
MNNAM EQU PNTRS+13  MNEMONIC TABLE NAME:SC:LU 
BRNAM EQU PNTRS+18  BRANCH TABLE NAME:SC:LU 
FWAMM EQU PNTRS+23  POINTER TO START OF MNEMONIC TABLE
FWAMB EQU PNTRS+24  POINTER TO START OF BRANCH TABLE
.OTBF EQU PNTRS+25  POINTER TO OUTPUT BUFFER 
OCCNT EQU PNTRS+26  OUTPUT CHARACTER COUNT
OTBFA EQU PNTRS+27  POINTER INTO OUTPUT BUFFER
LUOUT EQU PNTRS+28  CURRENT OUTPUT L.U. # 
LUINP EQU PNTRS+29  CURRENT INPUT L.U. #
SIGN  EQU PNTRS+30  SIGN OF CURRENT NUMBER
BLANK EQU PNTRS+31  CURRENT TERMINATION CHAR
REC#  EQU PNTRS+32  COMMAND FILE RECORD NUMBER
FLTYP EQU PNTRS+33  TYPE 0 FILE FLAG
TTYPR EQU PNTRS+34  CONSOLE TTY L.U. #
PRINT EQU PNTRS+35  LISTING L.U. #
READR EQU PNTRS+36  AUXILLIARY INPUT L.U. # 
PUNCH EQU PNTRS+37  AUXILLIARY OUTPUT L.U. #
ERTTY EQU PNTRS+38  ERROR LIST OUTPUT L.U. #
DCB   EQU PNTRS+39  DATA CONTROL BLOCK ADDRESS
FILBK EQU PNTRS+40  FILE CONTROL BLOCK ADDRESS
PFLAG EQU PNTRS+41  SAVE,LOAD FILE FLAG 
LOLIM EQU PNTRS+42  LOW LIMITS OF PROGRAM 
HILIM EQU PNTRS+43  HIGH LIMITS OF PROGRAM
LORUN EQU PNTRS+44  LOW RUN LIMITS
HIRUN EQU PNTRS+45  HIGH RUN LIMITS 
SLSTM EQU PNTRS+46  EXECUTE SLOW STMTS
LOTRC EQU PNTRS+47  LOW TRACE LIMITS
HITRC EQU PNTRS+48  HIGH TRACE LIMITS 
BRKP1 EQU PNTRS+49  BREAK POINT #1
BRKP2 EQU PNTRS+50  BREAK POINT #2
BRKP3 EQU PNTRS+51  BREAK POINT #3
BRKP4 EQU PNTRS+52  BREAK POINT #4
SMFLG EQU PNTRS+53  SIMULATE FLAG 
TYPE  EQU PNTRS+54  PARTIAL LINE CHARACTER COUNT
DLMTR EQU PNTRS+55  CHAR EDIT DELIMITER 
MERGF EQU PNTRS+56  MERGE FLAG
COMN  EQU PNTRS+57  COMMAND FILE NAME 
MANT1 EQU PNTRS+60  MANTISSA #1 
MANT2 EQU PNTRS+61  MANTISSA #2 
EXPNT EQU PNTRS+62  EXPONENT
INLOC EQU PNTRS+63  INV. LOC. LU,STRK,#TKRS BR. 
INTKZ EQU PNTRS+64  TRACK SIZE ON DISC FOR INV. BR. 
HSTPT EQU PNTRS+65  HIGH-STACK POINTER         BR.
TSTPT EQU PNTRS+66  TEMPORARY STACK POINTER    BR.
LSTPT EQU PNTRS+67  LOW-STACK POINTER          BR.
LSTAK EQU PNTRS+68  LOW-STACK ADDRESS          BR.
PRADD EQU PNTRS+69  PROGRAM EXECUTION          BR.
DSTRT EQU PNTRS+70  DATA                       BR.
NXTDT EQU PNTRS+71    STATEMENT                BR.
DCCNT EQU PNTRS+72      POINTERS               BR.
NXTST EQU PNTRS+73      NEXT STMT NUMBER 
TRAPF EQU PNTRS+74  TRAP BUSY FLAG *2040*800803*
      SKP 
      SUP PRESS MULTIPLE LISTINGS 
      SPC 1 
TEMPT BSS 14
.2    DEC 2 
.3    DEC 3 
.7    DEC 7 
.8    DEC 8 
.5    DEC 5 
.10   DEC 10
.15   DEC 15
.32   DEC 32
.40   DEC 40
.41   DEC 41
.43   DEC 43
.44   DEC 44
.45   DEC 45
.46   DEC 46
.47   DEC 47
.48   DEC 48
.58   DEC 58
.9999 DEC 9999
B37   OCT 37
B42   OCT 42
B44   OCT 44
B53   OCT 53
B54   OCT 54
B73   OCT 73
B133  OCT 133 
B135  OCT 135 
B177  OCT 177 
B200  OCT 200 
B2000 OCT 2000
MSK0  OCT 377 
MSK1  OCT 777 
M1400 OCT 176400
B3000 OCT 3000
B4000 OCT 4000
LF    OCT 5000
B1400 OCT 14000 
UNMNC OCT 21000 
B2200 OCT 22000 
B2300 OCT 23000 
LETOP OCT 72000 
RDOP  OCT 52000 
SPLOP OCT 65000 
OPMSK OCT 77000 
OPDMK OCT 100777
FRMSK OCT 100757
TABCN OCT 100037
M1    DEC -1
M2    DEC -2
M3    DEC -3
M4    DEC -4
M7    DEC -7
M8    DEC -8
M9    DEC -9
M16   DEC -16 
M32   DEC -32 
D53   OCT -53 
D100  OCT -100
M256  DEC -256
MAXSN DEC -10000
FN    ASC 1,FN
MNEG  OCT 100000   MAXIMUM NEGATIVE FLOATING
      OCT 376         POINT NUMBER
FLGBT EQU MNEG
ERBS  DEF ERR-1 
STBAS DEF SYNTB-28,I   28 IS OFSET FROM OP CODE B34(FIRST STMT OPCODE)
      SKP 
**********************************
*                                *
* PRINT NAME TABLE FOR OPERATORS *
*                                *
**********************************
QUOTE OCT 1000      BITS 15-9 OF THE LABELLED WORD
      ASC 1," 
COMMA OCT 2000      ARE THE BASIC CODE OPERATOR 
      ASC 1,, 
SMCLN OCT 3000      NUMBERS.  BITS 3-0 ARE THE
      ASC 1,; 
RPARN OCT 4001      OPERATOR'S HIERARCHICAL 
      ASC 1,) 
RBRAC OCT 5001      PRECEDENCE FOR THOSE OPERATORS
      ASC 1,] 
SCMMA OCT 6002      BELONGING TO FORMULAS.  THE 
      ASC 1,, 
ASSOP OCT 7002      UNLABELLED WORD GIVES THE 
      ASC 1,= 
PLUS  OCT 10007     ASCII REPRESENTATION OF THE 
      ASC 1,+ 
MINUS OCT 11007     SINGLE CHARACTER OPERATORS. 
      ASC 1,- 
TIMES OCT 12010 
      ASC 1,* 
DIV   OCT 13010 
      ASC 1,/ 
EXPS  OCT 14012 
      ASC 1,^ 
GTR   OCT 15005 
      ASC 1,> 
LSS   OCT 16005 
      ASC 1,< 
UNEQL OCT 17005 
      ASC 1,# 
EQUAL OCT 20005 
      ASC 1,= 
UNMIN OCT 21011 
      ASC 1,- 
LBRAC OCT 22020 
      ASC 1,[ 
LPARN OCT 23020 
      ASC 1,( 
UPLUS OCT 24011 
      ASC 1,+ 
OROP  OCT 25003 
MSFLG NOP 
ANDOP OCT 26004 
DFLAG NOP 
NOTOP OCT 27011 
PRFLG NOP 
GTREQ OCT 30005 
UFLAG NOP 
LSSEQ OCT 31005 
      NOP 
MINOP OCT 32006 
      NOP 
MAXOP OCT 33006 
      SKP 
* 
DIM   OCT 71003 
      ASC 2,DIM 
COM   OCT 34003 
      ASC 2,COM 
DEF   OCT 35003 
      ASC 2,DEF 
REM   OCT 36003 
      ASC 2,REM 
IF    OCT 40002 
      ASC 1,IF
FOR   OCT 41003 
      ASC 2,FOR 
NEXT  OCT 42004 
      ASC 2,NEXT
END   OCT 45003 
      ASC 2,END 
DATA  OCT 51004 
      ASC 2,DATA
IMAGE OCT 67005 
      ASC 3,IMAGE 
* 
LET   OCT 72003     THESE STATEMENTS MAY FOLLOW AN
      ASC 2,LET 
GOTO  OCT 37004       'IF' OPERATOR 
      ASC 2,GOTO
GOSUB OCT 43005 
      ASC 3,GOSUB 
RTRN  OCT 44006 
      ASC 3,RETURN
STP   OCT 46004 
      ASC 2,STOP
WAIT  OCT 47004 
      ASC 2,WAIT
CALL  OCT 50004 
      ASC 2,CALL
READ  OCT 52004 
      ASC 2,READ
PRNT  OCT 53005 
      ASC 3,PRINT 
INPUT OCT 54005 
      ASC 3,INPUT 
RSTOR OCT 55007 
      ASC 4,RESTORE 
PAUSE OCT 56005 
      ASC 3,PAUSE 
ASSN  OCT 62006 
      ASC 3,ASSIGN
FILS  OCT 63005 
      ASC 3,FILES 
CHAIN OCT 64005 
      ASC 3,CHAIN 
TRAP  OCT 66004 
      ASC 2,TRAP
INVK  OCT 70006 
      ASC 3,INVOKE
* 
FAIL  OCT 57005 
      ASC 3,FAIL: 
THEN  OCT 60004 
      ASC 2,THEN
* 
USING OCT 61005 
      ASC 3,USING 
* 
TO    OCT 75002 
      ASC 1,TO
STEP  OCT 76004 
      ASC 2,STEP
OF    OCT 77002 
      ASC 1,OF
NOT   OCT 27003 
      ASC 2,NOT 
AND   OCT 26003 
      ASC 2,AND 
OR    OCT 25002 
      ASC 1,OR
* 
GTE   OCT 30002 
      ASC 1,>=
LTE   OCT 31002 
      ASC 1,<=
AUNEQ OCT 17002     ALTERNATE UNEQUAL SIGN
      ASC 1,<>
MIN   OCT 32003 
      ASC 2,MIN 
MAX   OCT 33003 
      ASC 2,MAX 
* 
LEN   OCT 3 
      ASC 2,LEN 
      SKP 
************************************* 
*                                   * 
* BRANCH TABLE FOR STATEMENT SYNTAX * 
*  (THIS TABLE IS ORDERED BY OPCODES* 
*  STARTING AT OPCODE B34)          * 
*                                   * 
************************************* 
SYNTB DEF COMS     COM
      DEF DEFS     DEF
      DEF REMS     REM
      DEF GOTOS    GO TO
      DEF IFS      IF 
      DEF FORS     FOR
      DEF NXTS      NEXT
      DEF GOTOS    GOSUB
      DEF ENDS     RETURN 
      DEF ENDS     END
      DEF ENDS     STOP 
      DEF WAITS    WAIT 
      DEF CALLS    CALL 
      DEF DATAS    DATA 
      DEF READS    READ 
      DEF PRINS    PRINT
      DEF INPTS    INPUT
      DEF RSTRS    RESTORE
      DEF PAUS     PAUSE
      DEF SYNE2-1  FAIL 
      DEF SYNE2-1  THEN 
      DEF SYNE2-1  USING
      DEF ASSNG    ASSIGN 
      DEF FILES    FILES
      DEF CHANS    CHAIN
      NOP           SPCECIAL SYNTAX 
      DEF TRAPS     TRAP
      DEF REMS      IMAGE 
      DEF INVOK     INVOKE
      DEF DIMS     LET
      DEF LETS     DIM
      SPC 1 
* 
#STND DEC -28       # STANDARD OPERATORS IN TABLE 
* 
#PSIF DEC -16       # OPERATORS ALLOWED PAST 'IF' 
* 
      SKP 
*********************************** 
*                                 * 
*  CHECK SYNTAX AND TRANSLITERATE * 
*                                 * 
*********************************** 
BASC1 NOP 
      LDA PFLAG     IS THIS INITIALIZATION?*****
      CPA .9999 
      RSS           YES, GO GET SEGMENT'S FWAM AND LWAM 
      JMP BAS1C     NO, CONTINUE EXECUTION
      JSB GMS.C 
      JMP ROTAT     RET. TO MAIN FOR FWAM AND LWAM CHECK***** 
* 
* 
BAS1C LDA SBPTR,I   GET FIRST CHAR IN BUFFER
      SPC 1 
*  DETERMINE SEQUENCE NUMBER
      SPC 1 
SYNTX CPA .45       MINUS SIGN(DELETE CURRENT LINE)?
      JMP DLLIN     YES 
      JSB INTCK     RECORD
      DEF MAXSN       SEQUENCE NUMBER 
      JMP SYE25 
      STA TEMP3     SAVE CHAR 
      LDA LOLIM     IS SEQUENCE 
      CMA,INA         NUMBER >= 
      ADA 1             TO THE
      SSA                 LOW LIMIT?
      JMP PEXMK     NO, IGNORE STMT 
      LDA 1         IS SEQUENCE 
      CMA,INA         NUMBER <= 
      ADA HILIM         TO THE
      SSA                 HIGH LIMIT? 
      JMP PEXMK     NO, IGNORE STMT 
      STB .LNUM     SAVE LINE NUMBER
* 
      LDA MNNAM     IS THERE
      SZA             A MNEMONIC TABLE? 
      JMP *+3       YES!
      CCA           SET COUNT TO
      STA FWAMM,I     INDICATE NO ENTRIES 
* 
      LDB FWAMM     SET UP
      INB             SEARCH
      STB SUBS1         POINTERS
      STB SUBS2 
      STB SUBS3 
      STB SUBS4 
      LDA TEMP3     RECOVER CHAR 
      ISZ SBPTR     SAVE SPACE FOR LENGTH WORDR;
      LDB SBUFA     SET 
      INB             TEMP TO 
      STB TEMP          (SBUFF)+1 
      SPC 1 
* DETERMINE STATEMENT TYPE
      SPC 1 
      CPA .10       NULL STATEMENT? 
      JMP DLSTM     DELETE STATEMENT! 
      LDB #STND     -# OF STANDARD MNEMONICSR 
      JSB TBSRH     FIND STATEMENT TYPE 
       DEF DIM      START AT TOP OF LIST
       RSS          NO ERROR IF NOT FOUND 
      JMP PSTIF     FOUND 
      LDB SPNCT     IS THERE ANY
      SZB,RSS         SPECIAL SYNTAX? 
      JMP SUBR      NO! 
      JSB TBSRH     YES, LOOK UP IN SPECIAL 
       DEF SPTBL      IN SPECIAL
       RSS              SYNTAX TABLE
      JMP PSTIF 
SUBR  LDB FWAMM,I   GET MNEM COUNT
      JSB TBSRH     LOOK IN MNEMONIC TABLE
SUBS1  DEF 0
       JMP TRYLT    TRY LET STATEMENT 
PSTIF LDB M9        SET MULTIPLE STORE
      STB MSFLG       TO FALSE
      LDB PBPTR     NULL
      CPB PBUFF      PROGRAM? 
      RSS 
      JMP SYNT1     NO
      LDB FWAM      INSURE NO 
      STB PBUFF      SPURIOUS COMMON
      STB PBPTR       EXISTS
SYNT1 STB TEMPS       POINTER 
      CLB           SET DEFINE FLAG 
      STB DFLAG       TO FALSE
      STB PRFLG     SET PARAMETER FLAG TO FALSE 
      STB FROMF     SET FROM FLAG CLEAR 
      STA 1 
* 
      LDA SBPTR,I   GET OP CODE 
      AND OPMSK     IS THIS 
      CPA SPLOP       AN OP CODE FOR SPEC SYNTAX? 
      RSS           YES!
      JMP SYNT5     NO! 
      LDB COUNT     TABLE ORDINAL POSITION
      JSB SPEC1     GO AND PROCESS SPEC SYNTAX
       JMP ACTST    ACCEPT GOOD STATEMENT 
       JMP OUTER      OR IF BAD OUTPUT ERROR MESSAGE
SYNT5 LDA FWAMM     IS ENTRY IN 
      CMA,INA        THE STANDARD BASIC 
      ADA TBLPT       STATEMENT TABLE?
      SSA,RSS       NAMED SUBROUTINE? 
      JMP NMSBR     YES 
      LSR 9         COMPUTE ADDRESS OF SYNTAX 
      STB SFLAG     SET STRING FLAG TO OFF
      ADB STBAS         ROUTINE AND 
      JMP 1,I               BRANCH TO IT
**
***   TRY IMPLIED LET 
**
TRYLT LDB M1        SET TO SMALL NEG. NO. 
      STB TBLPT      SO TO SKIP NAMED SUB. SYNTAX 
      JSB BCKSP     BACK UP TO START FORMULA PROCESSOR
      LDA LETOP 
      STA SBPTR,I   DUB IN "LET" CODE 
      JMP PSTIF 
      SKP 
**
* 
***                      ***
**  LET STATEMENT SYNTAX  **
***                      ***
* 
LETS  LDA SBPTR     ENABLE STRING 
      STA SFLAG       VARIABLE
      ISZ MSFLG     SET MULTIPLE STORE FLAG ON
      JSB FSC       FETCH FORMULA 
      ISZ SFLAG     STRING VARIABLE FOUND?
      JMP LET1      NO! 
      JSB SYMCK     YES, DEMAND ASSIGNMENT OPERATOR!
       DEF ASSOP-1
      JMP SYNE2-1   NO ASSIGNMENT OPERATOR! 
      JSB RSTOP     RECORD STRING OPERATOR
      JSB SNULL     RECORD END-OF-FORMULA 
      JMP EOST      DEMAND END
      SPC 1 
LET1  ISZ SFLAG     DID STORE OCCUR?
      JSB ERROR     NO
SYNE2 EQU * 
* 
******************************
*                            *
* CHECK FOR END OF STATEMENT *
*                            *
******************************
EOST  CPA .10       END OF STATEMENT? 
      JMP ACTST     YES,ACCEPT STATEMENT! 
NOEOF JSB ERROR     CHARACTERS AFTER LEGAL END-OF-STATEMENT 
***************************** 
*                           * 
*   CALL STATEMENT SYNTAX   * 
*                           * 
***************************** 
* 
*  THE CALL SYNTAX CHECK MAKES EXTENSIVE USE OF THE MNEMONIC AND
*  BRANCH TABLES TO DETERMINE THE CORRECTNESS OF THE SUBROUTINE 
*  CALL AND THE ORDINAL POSITION OF THE SUBROUTINE WITHIN THE 
*  BRANCH TABLE, SO THAT THE EXECUTE SEGMENT OF BASIC CAN COMPUTE 
*  THE ADDRESS OF THE SUBROUTINE. CERTAIN ERRORS CAN BE CAUSED
*  BY THE INCORRECT USE OF PARAMETERS IN THE CALLING SEQUENCE OF
*  A SUBROUTINE. BELOW IS A SIMPLE TABLE INDICATING LEGAL PARAMETERS: 
* 
* 
*                                DIRECTION OF PARAMETER TRANSFER
*         +---------------------------------------------------+ 
*         ! TYPE OF PARAMETER ! BASIC TO SUB. ! SUB. TO BASIC ! 
*         +---------------------------------------------------! 
*         ! SIMPLE VARIABLE   !     LEGAL     !     LEGAL     ! 
*         +---------------------------------------------------+ 
*         !   CONSTANT        !     LEGAL     !    ILLEGAL    ! 
*         +---------------------------------------------------+ 
*         !  ARRAY VARIABLE   !     LEGAL     !     LEGAL     ! 
*         +---------------------------------------------------+ 
*         !  ARRAY ELEMENT    !     LEGAL     !     LEGAL     ! 
*         +---------------------------------------------------+ 
*         !  STRING VARIABLE  !     LEGAL     !     LEGAL     ! 
*         +---------------------------------------------------+ 
*         !  STRING CONSTANT  !     LEGAL     !    ILLEGAL    ! 
*         +---------------------------------------------------+ 
*         !  EXPRESION        !     LEGAL     !    ILLEGAL    ! 
*         +---------------------------------------------------+ 
* 
* 
* 
*  THE MNEMONIC TABLE CONTAINS THE ASCII NAME OF THE SUBROUTINE,
*  THE NUMBER OF CHARACTERS IN THE SUBROUTINE, AND THE NUMBER OF
*  PARAMETERS IN THE SUBROUTINE CALLING SEQUENCE. THE FORMAT OF 
*  EACH ENTRY IS SHOWN BELOW. 
* 
* 
*           15                              0 
*           +-------------------------------+ 
*           !F!V! ! ! ! ! ! !P!P!P!P!C!C!C!C! 
*           +-------------------------------+ 
*           ! 1ST CHARACTER ! 2ND CHARACTER ! 
*           +-------------------------------+ 
*           ! 3RD CHARACTER !    ETC.       ! 
*           +-------------------------------+ 
* 
*      WHERE :
*                 F     =  1 IF FUNCTION
*                 F     =  0 IF SUBROUTINE
*                 V     =  1 IF VARIABLE LENGTH PARAMETER LIST
*                 V     =  0 IF FIXED NUMBER OF PARAMETERS
*                 PPPP  =  NUMBER OF PARAMTERS
*                 CCCC  =  NUMBER OF CHARACTERS IN NAME 
* 
* 
*  THE BRANCH TABLE CONTAINS INFORMATION REGARDING THE ADDRESS
*  OF THE SUBROUTINE, PARAMETER CONVERSION (REAL TO INTEGER OR
*  INTEGER TO REAL), TYPE OF PARAMETER, AND DIRECTION THAT THE
*  PARAMETER IS REUIRED TO GO ( BASIC TO SUBROUTINE OR SUBROUTINE 
*  TO BASIC). 
* 
* 
*           15                             0
*           +-------------------------------+ 
*           !D!D!D!D!D!P!P!P!P!P!S!S!S!S!S!S! ADDRESS 
*           +-------------------------------+ 
*           !X!A!A!A!A!A!A!A!A!A!A!A!A!A!A!A! ARRAY 
*           +-------------------------------+ 
*           !X!T!T!T!T!T!T!T!T!T!T!T!T!T!T!T! TO FROM 
*           +-------------------------------+ 
*           !F!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!   CONVERSION
*           +-------------------------------+ 
* 
* 
*    WHERE: 
*             DDDDD  =  IDENTIFICATION LETTER 
*             PPPPP  =  OVERLAY NUMBER
*             SSSSSS =  SUBROUTINE NUMBER WITHIN OVERLAY
*             A      =  1 IF ARRAY, 0 IF NON-ARRAY
*             T      =  1 IF FROM SUBROUTINE, 0 IF TO SUBROUTINE
*             F      =  1 IF INTEGER FUNCTION 
*             F      =  0 IF REAL FUNCTION
*             I      =  1 IF CONVERSION TO INTEGER REQUIRED 
*             I      =  0 IF NO CONVERSION REQUIRED 
*             X      =  BIT POSITION NOT USED 
* 
* 
* 
CALLS JSB GETCR     FETCH AND 
       JMP NOEOF      RECORD
      LDB FWAMM,I   GET MNEM COUNT
      JSB TBSRH     LOOK FOR SUBROUTINE NAME
SUBS2  DEF 0
       JSB ERROR    NOT FOUND 
CALER JMP PSTIF     DO POST-IF STATEMENT
* 
**
*** NAMED SUBROUTINE SYNTAX (NO 'CALL' PREFIX)
**
NMSBR CLA           SET TO
      STA TEMP7       INDICATE SUBROUTINE 
* GET FIRST WORD OF MNEMONIC TBL ENTRY
      LDA PRPTR,I   IS THIS 
      SSA             REALLY A SUBROUTINE?
      JSB ERROR     NO! 
SYNE3 EQU * 
FUNCT STA TEMP6     SAVE PARAMETER WORD 
      RRR 4           COUNT 
      AND .15           FROM
      CMA 
      STA PCNT
      CMA 
*                         BEING DESTROYED 
*                           BY FSC
      LSL 9         LEFT JUSTIFY COUNT
      STA TEMP3       FOR INTERP. CODE
      LDA FWAMM,I   COMPUTE OFFSET IN MNEMONIC TBL
      CMA,INA 
      ADA COUNT     AND SAVE IT FOR LATER 
      STA TCCNT     THIS ORDINAL POSITION OF SUB. ENTRY 
      LDB TEMP6     FORTRAN 
      SSB             FUNCTION? 
      JMP CALL1     YES!
      ADA B5000     NO, ADD IN CALL OP CODE 
CALL4 STA SBPTR,I   STORE IN INTERP. CODE 
      ISZ SBPTR     UPDATE INTERP. CODE PTR.
      LDA COMMA     COMMA CODE
      STA SBPTR,I   STUFF IT (WIPE OUT LEFT PAREN)
      ISZ PCNT      NO! 
      JMP NAMSB 
* 
      LDB B4000     FUDGE A RIGHT PAREN 
      STB SBPTR,I 
      LDA TEMP6     DID WE PROCESS A
      SSA               FUNCTION
      JMP FSC10+1   YES!
      JSB GETCR     FETCH NEXT CHARACTER
      LDA .10 
      ISZ SBPTR 
      JMP CALL5 
* 
CALL1 ADA TEMP3     STUFF IN
      JMP CALL4       PARM COUNT INSTEAD OF B50000
* 
* 
CALL2 CCB 
      JSB SYMCK     COMMA?
       DEF COMMA-1
       JMP CALL3    NO
      ISZ PCNT       YES, MORE PARAMS ALLOWED ? 
      JMP PRMCK     YES, LOOK FOR PARAMETER.
SYE11 JSB ERROR     NO,TOO MANY PARMETERS 
* 
* 
*     PROCESS SUBROUTINE AND FUNCTION PARAMETERS
* 
NAMSB LDA TCCNT     GET ORDINAL NUMBER
      ALS,ALS         AND MULTIPLY BY 4 
      ADA .2            AND ADD 2 TO GET
      ADA FWAMB           POSITION IN BRANCH TBL THEN 
      LDA 0,I               GET THE TO/FROM PARAMETER WORD
      STA TOFRM     SAVE FOR CHECKING EACH PARAMETER
PRMCK LDA TOFRM     GET TO/FROM WORD
      CCB 
      SLA,RSS       IS IT SET?
      CLB           NO! THEN SET THE FLAG TO 0
      STB FROMF     YES! THEN SET IT NON-ZERO 
      ARS           SHIFT TO
      STA TOFRM       FOR NEXT PARAMETER
      JSB GETCR     GET THE FIRST PARAMETER CHARACTER 
      LDA .10 
      CPA B42       IS IT A STRING LITERAL? 
      JMP CALL6     YES!
      JSB LETCK     IS IT A LETTER? 
      JSB PERR      NO, CHECK FOR PARAMETER ERROR 
      JSB BCKSP     NO, PUT CHAR BACK 
      JSB FRCUR     SAVE VARIABLES
      LDA SBPTR     SET TO
      STA SFLAG       ALLOW STRING VARIABLES
      JSB FSC       FETCH 
      CLB           CLEAR 
      STB FROMF     TO/FROM FLAG
      ISZ SFLAG     STRING? 
      RSS           NO! 
      JMP CALL7     YES!
CALL8 JSB FPOP      RESTORE VARIABLES 
      JMP CALL2       PARAMETER FORMULA 
* 
CALL3 ISZ PCNT      MORE PARAMETERS EXPECTED? 
      RSS           YES 
      JMP CALL9     NO! 
      LDB TEMP6     DOES THIS 
      RBL             ROUTINE EXPECT
      SSB,RSS           VARIABLE LENGTH LIST
      JMP SYE11     NO! 
CALL9 JSB RPCK      FETCH RIGHT PARENTHESIS 
      LDB TEMP6     FORTRAN FUNCTION
      SSB               BEING PROCESSED?
      JMP FSC19     YES, COMPLETE SYNTAX CHECK
* 
CALL5 CCB 
      JSB TBSRH     IS CALL FOLLOWED BY "FAIL:"?
       DEF FAIL 
       JMP EOST 
      JSB GETCR     YES. ANALYZE REST OF STMT.
       JMP NOEOF
      ISZ SBPTR 
      JMP FAILS 
* 
CALL6 JSB PERR      CHECK FOR PARAMETER ERROR 
      ISZ SBPTR     POINT AT PLACE TO PUT " OPERATOR
      CCB 
      JSB SYMCK     PUT IN " OPERATOR 
       DEF QUOTE-1
       NOP
      LDA B42       SPECIFY STRING TERMINATOR 
      JSB CHRST     PUT STRING IN INTERP CODE 
      JSB SNULL     ADD NULL AFTER STRING CONSTANT
      JSB GETCR     FETCH NEXT CHARACTER
      LDA .10 
      JMP CALL2 
* 
CALL7 JSB SNULL     PUT NULL AFTER STRING 
      CCB 
      STB SFLAG     RESET SFLAG 
      JMP CALL8 
* 
* 
* A CHECK IS MADE HERE TO SEE IF THE SUBROUTINE PARAMETER 
* (A STRING LITERAL, CONSTANT OR EXPRESSION) IS BEING 
* RETURNED FROM A SUBROUTINE AS INDICATED BY THE BRANCH TABLE 
* 
PERR  NOP 
      LDB FROMF     FLAG
      SZB,RSS         SET?
      JMP PERR,I    NO! 
      CPA .41       RIGHT PAREN?
      JMP PERR,I    YES, OK THEN! 
      CPA B135      RIGHT BRACKET?
      JMP PERR,I    YES, OK 
      CPA B54       COMMA?
      JMP PERR,I    YES, OK THEN! 
      CLA           CLEAR 
      STA FROMF       FROM FLAG 
      JSB ERROR     NO, ILLEGAL PARAMETER 
SYE16 EQU * 
B5000 OCT 50000 
      SKP 
* 
********************
*                  *
*  TRAP STATEMENT  *
*                  *
********************
* 
TRAPS CCB           SET FOR 
      STB CCODE       NEG SEQ NUMBER CASE 
      JSB FSC       FETCH TRAP # FORMULA
      CPA .10       END-OF-STATEMENT? 
      JMP SYNE6-1   YES 
      CCB           GET 
      JSB TBSRH       GOSUB SYNTAX
      DEF GOSUB 
      JSB ERROR     NOT FOUND 
SYNE6 JSB GETCR     CHECK 
      NOP             FOR (-) SIGN
      CPA .45       IS IT?
      JMP TRAP1     YES!
      JSB BCKSP     GET BACK TO LAST CHAR 
TRAP2 CCB           SET FOR 
      STB RFLAG       ERROR RETURN HERE 
      JSB PRGIN     GET SEQUENCE NUMBER 
      DEF MAXSN 
      RSS           GOOD RETURN 
      JSB CKZER     IS NUMBER=0?
      JSB BCKUP     BACK UP TO SEQ NUMBER 
      LDB SBPTR,I   NEGATE
      ISZ CCODE       SEQUENCE NUMBER 
      CMB,INB 
      STB SBPTR,I       IF NECESSARY
      ISZ SBPTR     RESET PTR 
      JMP EOST      END-OF-STATEMENT PROCESSING 
* 
TRAP1 CLB           SET FOR 
      STB CCODE       (-) FOUND 
      JMP TRAP2 
* 
CKZER NOP           IF
      SZB             B=0 
      JMP SYE25         THEN STORE
      STB SBPTR,I         IT IN INTERP. 
      ISZ SBPTR             ELSE PRINT
      JMP CKZER,I             ERROR MESSAGE 
*