Intel 9800758-02 manual Merge, New

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Commands and Statements

BASIC-80

cannot later be assigned values with the LET statement. This is because strings are assigned new storage locations when given new values and this destroys the effect of the FIELD statement. Accordingly, the LSET and RSET statements must be used to assign new values. These commands may also be used with normal string statements. If the assigned string value is shorter than the space reserved for the string variable in the FIELD statement, LSET left justifies the string, adding blanks (ASCII 20H) as needed. RSf:T right justifies the string in the same way. If the string is longer than the space reserved, the extra characters are ignored. LSET and RSET may be used with string variables that have not been fielded. Unlike normal string assignment, the length of the receiving string is not changed by an LSET or RSET assignment.

LSET string variable = string expression

RSET string variable = string expression

10A$ = "1 23456"

20RSET A$ = "A B"

30PRINT A$; "X"

40LSET A$ = "C 0"

50PRINT A$; "X"

RUN

ABX

CO X

Ok

MERGE

The MERGE command reads a program from disk and combines it with the current program without changing line numbers of either program. If the new program and the current program have instruction lines with the same line numbers, the new in- struction lines replace the current ones. The new program must have been saved in ASCII format. MERGE sets all variables and arrays to zero. If used within a pro- gram, the program will end. A given string expression must resolve to an ISIS-II filename.

MERGE string expression

MERGE ":F4: EVAL.BAS"

Ok

NEW

The NEW command deletes the current program and clears all variables and arrays. If a program has not been saved and the NEW command is given, the program is lost.

NEW

In the sample program below, the program has been deleted by the NEW command. The LIST command will not list it, or any program, until another is read from a peripheral device or entered line-by-line.

240PRINT "end of program"

250PRINT

260PRINT

270END

NEW Ok

LIST Ok

6-12

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Contents BASIC-SO Reference Manual A108/0979/7500 FL Preface Page Contents Illustrations Chapter Introduction to BASIC-80 Invoking BASIC-80Examples Introduction to BASIC-80Basic filename MEMTOPaddress FilenameListing the Directory of a Disk Renaming a FileChanging File Attributes Deleting a FileYou can now run, list, or edit the program Save LP ,ACommands StatementsBASIC-80 Commands Contd BASIC-80 StatementsBASIC-80 Statements Contd BASIC-80 FunctionsBASIC-80 Functions Contd Representing Data FunctionsConstants Integer ConstantsDecimal Integer Constants Hexadecimal Integer ConstantsSingle-Precision Floating-Point Constants Octal Integer ConstantsDouble-Precision Floating-Point Constants String Constants String VariablesThis is a string constant $ = Enter next data stringL4! = Csng l4 YI,1String Arrays Arithmetic Operators BASIC-SO Operators in Order of Precedence ContdLogical Operators String OperatorNumeric Expressions String ExpressionsEntering and Editing Programs 30 A=8*52 30 A=830 A=8*52 30 A=8*37 30 A--=8xx*522537 Control-R a = 8*37Subcommand Command 3D press 3, then D resultsInteger D If AB thenIf AB then 120 Else Null SET Syntax of the X subcommand is At this point, the other editing subcommands may be usedPrint Undefined SET The E subcommand is entered Integer C character characterMove the cursor to PRINT. Enter 2C RE L Print Undefined SET. Enter a LSyntax Error Messages BASIC-80 Error MessagesOverflow, Underflow, and Divide-by-Zero Error Trapping Trace Facility Error Simulation Error HandlingRestarting Program Execution If line 40 is replaced withOpening a Sequential File Open 1,#1,F1DATESRefer to for further details of Print Using Writing to a Sequential FileReading from a Sequential File If executed four times, it would read all eight valuesClosing a Sequential File Value of R$ would beDefining a Random 1/0 Field-FIELD BuffersField #3, 20 AS N$ Disk File Input/Output Field #3, 20 AS N$, 9 AS SS$Opening and Closing a Random Disk File Reading from a Random 1/0 FileAny of the parameters can be variables To read the next recordWriting to a Random 1/0 File IntegerSingle-precision value Double-precision valueMKI$ Attrib Fdrive numberfilename, W1 Attrib Fdrive numberfilename, WOAuto first lineJ, increment Clear expression,addressCommands and Statements CloseDEF FNX Rules for function name are the same as for variable nameDefsng Defdbl Defstr Defint DIM DeleteError DIREdit ENDError expression ExitField FOR-NEXT-STEPGET GosubFor variable=expression to expression Step expression GET I file number ,record numberInput IF-THEN-ELSEGoto Kill LETLine Input ListLSET, Rset LoadMerge NEWNext 9 16On ... Goto On ... GosubOpen OUT Option BasePoke Print Print UsingString Fields Numeric fields If X$=SEVEN and Y$=EIGHT, the results of line 40 would bePrun PUTRandomize ReadREM Resume ReturnSave RUN line numberlstring expression ,FLine number RUN filename 60 ENDTRON, Troff ? 5,8,2Wait WidthABS ATNCint CHR$Functions Csng CVI CVS10 A# = 1.00/3.00 AO/o =Dskf EOFFIX Ok·INP HexsInputs Instr INTLEFT$ LEN LOCLOF LOGMKI$ MKS$ MKD$ MID$OCT$ Rights Peek expressionPOS integer RIGHT$ string,integerSGN SINSpaces 10 a =1SPC SPC integerIf A$ = 2 then Print Correct Else Goto SQRexpressionTAB expression STR$ expressionTAN expression Here is an example of how the USRn statement is used 60 AO/o =Appendix a BASIC-SO Error Codes Table A-I. BASIC-80 Error CodesTable A-I. BASIC-SO Error Codes Contd Appendix B BASIC-SO Reserved Words Page To halt program execution and return to command LevelTo tab across the line To resume program execution after it is stopped byPage Table D-l. Ascii Code List Appendix D Ascii CodesTable D-2. Ascii Code Definition BELAppendixe Calling Subroutines Figure B-1. Internal Representation of Numbers and Strings Some Real Examples RESULT=USR%1VARPTRA, VARPTRB, VARPTRC» PRINTA+B+C= ResultFigure E-2 /8085 Assembly Language Program Figure E-3. PL/M-80 Program Appendix F RMX/SO BASIC-SO Initializing the Predefined RMX/SO BASIC-SO Configuration ISIS-II BASIC-SOTable F-l. Sample Configuration Jumper Wiring OOOOH-OFFFHGenerating Boot-Loaded and PROM-Based Versions BASIC-80 Source FilesBASIC-80 Object Files BASIC-80 Executable FilesGenerating a Boot-Loaded RMX/80 BASIC-80 That are not boot loaded This option is used to allocate memory. It is 1 if the bootSetting baud rates, refer to the RMX/SO Users Guide This option enables your user-written I/O drivers if youISBC 80/20-4 Generating a PROM-Based RMX/80 BASIC-80 Prom F1 RMX820.L1BSTART, & FOBASCM.OBJ,& FORMXBAS.LlB F1 DFSDIR. L1BDIRECTORY ,RENAM E,& F1 MTI810.L1B Configuring DFS on an iSBC 80/10 Adding BASIC-SO to an Existing RMX/SO ConfigurationConfiguration Requirements ISBC SO/10 System ClockPublic Variables Adding User-Written I/O Drivers to RMX/SO BASIC-SO Open 0,#1, L1LlSTFigure F-S. Sample User-Written 1/0 Driver Routine Altering BASIC-80 Workspace Burning a BASIC-80 Program Into PromBaprom F1HEATER.BAS Page Index Ase BASIC-80 RIGHT$,7-1O Request for Readerscomments 111111