Intel 9800758-02 manual Get, Gosub, For variable=expression to expression Step expression

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Commands and Statements

BASIC-SO

If the TO expression is larger than the starting expression and the step expression is negative then the loop will not execute. Similarly, if the TO expression is less than the starting expression and the STEP expression is positive, then the loop will not execute. After the conclusion of the loop, variable A contains the first value not us- ed in the loop.

Control cannot be passed to a statement within a FOR ... NEXT loop with GO TO, GO SUB etc, but a GO TO can be used to jump out of a FOR ... NEXT loop. FOR ... NEXT loops may be nested so long as each inner loop is completely contained in all outer loop~, and they employ different index variables.

If possible, integer index variables should be used to speed execution. Double preci- sion index variables are not allowed.

FOR variable=expression TO expression [STEP expression]

10FOR A = 1 TO 5

20PRINT A* A,

30NEXT A

40 END

RUN

1 4 9 16 25

GET

The GET statement reads the specified sector from the specified file into 128- byte random buffer. The file must be open for random access. If the sector number is not specIfied, the sector number of the previous GET or PUT is incremented and this sector is read. A GET without a sector number immediately after a file is opened will return the first sector. The largest possible sector number is 2046. If the GET com- mand is issued for a sector that has not yet been written, buffer contents are undefined, and there is no error message. However, if no greater record has ever been PUT or GET, the file will be extended.

GET [I] file number [,record number]

10OPEN "R" ,#3, "F1 :PERSON" 20GET#3,1

30FIELD #3, 20 AS N$, 9 AS SS$

40 PRINT N$,SS$

RUN

JONES, JOHN J.

517317010

Ok

GOSUB

The GOSUB statement transfers program control to the line number specified as an argument. This line number is typically the first line number of a subroutine that is used several times during a program. The RETURN statement transfers control back to the first instruction that follows the last GOSUB statement executed.

GOSUB line number

10 lNPUT A

20IF A>O THEN GOSUB 100 ELSE PRINT "A MUST BE >0"

30GOTO 10

100PRINT SQR(AO);SIN(A);TAN(A)

110RETURN

6-8

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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 ConstantsOctal Integer Constants Single-Precision Floating-Point 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 LBASIC-80 Error Messages Syntax 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 beBuffers Defining a Random 1/0 Field-FIELDField #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 numberIF-THEN-ELSE InputGoto Kill LETLine Input ListLSET, Rset LoadMerge NEWNext 9 16On ... Gosub On ... GotoOpen Option Base OUTPoke Print Using PrintString 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 ATNCHR$ CintFunctions Csng CVI CVS10 A# = 1.00/3.00 AO/o =Dskf EOFFIX Ok·Hexs INPInputs INT InstrLEFT$ LEN LOCLOF LOGMID$ MKI$ MKS$ MKD$OCT$ Rights Peek expressionPOS integer RIGHT$ string,integerSGN SINSpaces 10 a =1SPC SPC integerIf A$ = 2 then Print Correct Else Goto SQRexpressionSTR$ expression TAB 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