Intel 9800758-02 manual Exit, Field, For-Next-Step, Error expression

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BASIC-SO

Commands and Statements

ERROR expression

10 INPUT A,B,C

12IF B=O THEN ERROR 11

14PRINT AlB

20END

RUN

? 40,0,17

DIVISION BY ZERO IN 12 Ok

EXIT

The EXIT command terminates operation of the BASIC-80 interpreter and returns control to ISIS-II. EXIT closes all open files, but does not automatically save pro- grams. If you EXIT without saving the current program, it will be lost.

EXIT

FIELD

The FIELD statement is used to allocate space within one of six 128-byte BASIC-80 random file buffers. When a random 110 transaction occurs, data move to or from the specified random file buffer to or from disk sectors. The FIELD statement associates the data with its position in the 110 buffer so that future references to the specified variable will access the proper string characters or numbers within the record stored in the random file buffer. The example below shows how FIELD is used. For further information, refer to the BASIC-80 Disk Input/Output section.

FIELD # file number,

number of characters AS string variable

[,number of characters AS string variable] ...

The program below opens random file :F1 :FILE.1 and asks for five 30-character strings to insert into :Fl :FILE.1.

10OPEN "R" ,#1, ":F1 :FILE.1"

20FIELD #1,30 AS A$

30FOR 1=1 to 5

40INPUT Z$

50LSET A$ = Z$

60PUT#1,1

70NEXT I

80CLOSE#1

90END

FOR-NEXT-STEP

The FOR-NEXT statement allows the execution of a given group of lines a given number of times. As shown in the example below, on each iteration of the routine, value A is incremented by the value given in the STEP instruction. If no value for STEP is specified, the increment is 1. The instruction lines following the line con- taining the FOR instruction are executed until the NEXT instruction is encountered. Program control returns to the FOR instruction line, STEP is added to the value of A, and the routine is reentered. When variable A exceeds the TO expression, control passes to the instruction line following the NEXT instruction line.

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Contents BASIC-SO Reference Manual A108/0979/7500 FL Preface Page Contents Illustrations Invoking BASIC-80 Chapter Introduction to BASIC-80Filename ExamplesIntroduction to BASIC-80 Basic filename MEMTOPaddressDeleting a File Listing the Directory of a DiskRenaming a File Changing File AttributesSave LP ,A You can now run, list, or edit the programStatements CommandsBASIC-80 Statements BASIC-80 Commands ContdBASIC-80 Functions BASIC-80 Statements ContdBASIC-80 Functions Contd Functions Representing DataHexadecimal Integer Constants ConstantsInteger Constants Decimal Integer ConstantsDouble-Precision Floating-Point Constants Octal Integer ConstantsSingle-Precision Floating-Point Constants $ = Enter next data string String ConstantsString Variables This is a string constantYI,1 L4! = Csng l4String Arrays BASIC-SO Operators in Order of Precedence Contd Arithmetic OperatorsString Expressions Logical OperatorsString Operator Numeric ExpressionsEntering and Editing Programs 30 A--=8xx*522537 Control-R a = 8*37 30 A=8*5230 A=8 30 A=8*52 30 A=8*37If AB then SubcommandCommand 3D press 3, then D results Integer DIf AB then 120 Else Null SET At this point, the other editing subcommands may be used Syntax of the X subcommand isPrint Undefined SET. Enter a L Print Undefined SET The E subcommand is enteredInteger C character character Move the cursor to PRINT. Enter 2C RE LOverflow, Underflow, and Divide-by-Zero BASIC-80 Error MessagesSyntax Error Messages Error Trapping Trace Facility If line 40 is replaced with Error SimulationError Handling Restarting Program ExecutionOpen 1,#1,F1DATES Opening a Sequential FileIf executed four times, it would read all eight values Refer to for further details of Print UsingWriting to a Sequential File Reading from a Sequential FileValue of R$ would be Closing a Sequential FileField #3, 20 AS N$ BuffersDefining a Random 1/0 Field-FIELD Field #3, 20 AS N$, 9 AS SS$ Disk File Input/OutputTo read the next record Opening and Closing a Random Disk FileReading from a Random 1/0 File Any of the parameters can be variablesDouble-precision value Writing to a Random 1/0 FileInteger Single-precision valueMKI$ Clear expression,address Attrib Fdrive numberfilename, W1Attrib Fdrive numberfilename, WO Auto first lineJ, incrementClose Commands and StatementsRules for function name are the same as for variable name DEF FNXDefsng Defdbl Defstr Defint Delete DIMEND ErrorDIR EditFOR-NEXT-STEP Error expressionExit FieldGET I file number ,record number GETGosub For variable=expression to expression Step expressionGoto IF-THEN-ELSEInput List KillLET Line InputLoad LSET, RsetNEW Merge9 16 NextOpen On ... GosubOn ... Goto Poke Option BaseOUT String Fields Print UsingPrint If X$=SEVEN and Y$=EIGHT, the results of line 40 would be Numeric fieldsPUT PrunRead RandomizeREM Return Resume60 END SaveRUN line numberlstring expression ,F Line number RUN filename? 5,8,2 TRON, TroffWidth WaitATN ABSFunctions CHR$Cint AO/o = CsngCVI CVS 10 A# = 1.00/3.00EOF DskfOk· FIXInputs HexsINP LEFT$ INTInstr LOG LENLOC LOFOCT$ MID$MKI$ MKS$ MKD$ RIGHT$ string,integer RightsPeek expression POS integer10 a =1 SGNSIN SpacesSQRexpression SPCSPC integer If A$ = 2 then Print Correct Else GotoTAN expression STR$ expressionTAB expression 60 AO/o = Here is an example of how the USRn statement is usedTable A-I. BASIC-80 Error Codes Appendix a BASIC-SO Error CodesTable A-I. BASIC-SO Error Codes Contd Appendix B BASIC-SO Reserved Words Page To resume program execution after it is stopped by To halt program execution and return to commandLevel To tab across the linePage Appendix D Ascii Codes Table D-l. Ascii Code ListBEL Table D-2. Ascii Code DefinitionAppendixe Calling Subroutines Figure B-1. Internal Representation of Numbers and Strings RESULT=USR%1VARPTRA, VARPTRB, VARPTRC» PRINTA+B+C= Result Some Real ExamplesFigure E-2 /8085 Assembly Language Program Figure E-3. PL/M-80 Program Appendix F RMX/SO BASIC-SO ISIS-II BASIC-SO Initializing the Predefined RMX/SO BASIC-SO ConfigurationOOOOH-OFFFH Table F-l. Sample Configuration Jumper WiringBASIC-80 Executable Files Generating Boot-Loaded and PROM-Based VersionsBASIC-80 Source Files BASIC-80 Object FilesGenerating a Boot-Loaded RMX/80 BASIC-80 This option enables your user-written I/O drivers if you That are not boot loadedThis option is used to allocate memory. It is 1 if the boot Setting baud rates, refer to the RMX/SO Users GuideISBC 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 ISBC SO/10 System Clock Configuring DFS on an iSBC 80/10Adding BASIC-SO to an Existing RMX/SO Configuration Configuration RequirementsPublic Variables Open 0,#1, L1LlST Adding User-Written I/O Drivers to RMX/SO BASIC-SOFigure F-S. Sample User-Written 1/0 Driver Routine Burning a BASIC-80 Program Into Prom Altering BASIC-80 WorkspaceBaprom F1HEATER.BAS Page Index Ase BASIC-80 RIGHT$,7-1O Request for Readerscomments 111111