Intel 9800758-02 manual Next, 9 16

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BASIC-80

Commands and Statements

NEXT

The NEXT statement is used with a previous FOR statement to end an iteration of a FOR-NEXT loop; when BASIC-SO encounters a NEXT statement, control passes back to the statement line containing the last FOR statement. If no index variable is specified, BASIC-SO increments the variable specified in the last FOR statement. Each NEXT can end more than one loop if the index variables used in each loop are given separated by commas.

The syntax of NEXT is:

NEXT [Variable] [, Variable] ...

10FOR A=1 TO 5

20PRINT A* A;

30NEXT A

40END

RUN

14 9 16 25

Ok

NULL

The NULL command specifies the number of null characters printed at the end of a printed line, following the carriage return. This feature is used with hard copy ter- minals that require a certain number of null characters that set carriage return timing.

NULL number of null characters to be transmitted

ON ERROR GOTO

The ON ERROR OOTO statement transfers program control to the specified line number when error conditions occur or an ERROR instruction simulates an error within a program. The ERR function is set to the applicable error code and the ERL function is set to the applicable line number.

The instruction line ON ERROR OOTO 0 removes the effect of any previous ON ERROR OOTO, so that errors cause messages to print and halt execution. If ON ERROR OOTO 0 is executed within an error-handling routine (after an error but before a RESUME) the proper error message prints and execution halts immediately.

If an error occurs in an error routine, after an ON ERROR OOTO branch and before a RESUME, the ON ERROR OOTO has no effect. This means that if an ON ERROR OOTO is in effect, and two errors (or ERROR commands) occur without an intervening RESUME, the second error prints an error message and halt execution.

ON ERROR GOTO line number

10 ON ERROR GOTO 200

20 ERROR 11

200 PRINT "ERROR" ERR "AT LINE" ERL

210 RESUME NEXT

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Contents BASIC-SO Reference Manual A108/0979/7500 FL Preface Page Contents Illustrations Invoking BASIC-80 Chapter Introduction to BASIC-80Introduction to BASIC-80 ExamplesBasic filename MEMTOPaddress FilenameRenaming a File Listing the Directory of a DiskChanging File Attributes Deleting a FileSave 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 DataInteger Constants ConstantsDecimal Integer Constants Hexadecimal Integer ConstantsDouble-Precision Floating-Point Constants Octal Integer ConstantsSingle-Precision Floating-Point Constants String Variables String ConstantsThis is a string constant $ = Enter next data stringYI,1 L4! = Csng l4String Arrays BASIC-SO Operators in Order of Precedence Contd Arithmetic OperatorsString Operator Logical OperatorsNumeric Expressions String ExpressionsEntering and Editing Programs 30 A=8 30 A=8*5230 A=8*52 30 A=8*37 30 A--=8xx*522537 Control-R a = 8*37Command 3D press 3, then D results SubcommandInteger D If AB thenIf AB then 120 Else Null SET At this point, the other editing subcommands may be used Syntax of the X subcommand isInteger C character character Print Undefined SET The E subcommand is enteredMove the cursor to PRINT. Enter 2C RE L Print Undefined SET. Enter a LOverflow, Underflow, and Divide-by-Zero BASIC-80 Error MessagesSyntax Error Messages Error Trapping Trace Facility Error Handling Error SimulationRestarting Program Execution If line 40 is replaced withOpen 1,#1,F1DATES Opening a Sequential FileWriting to a Sequential File Refer to for further details of Print UsingReading from a Sequential File If executed four times, it would read all eight valuesValue 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/OutputReading from a Random 1/0 File Opening and Closing a Random Disk FileAny of the parameters can be variables To read the next recordInteger Writing to a Random 1/0 FileSingle-precision value Double-precision valueMKI$ Attrib Fdrive numberfilename, WO Attrib Fdrive numberfilename, W1Auto first lineJ, increment Clear expression,addressClose Commands and StatementsRules for function name are the same as for variable name DEF FNXDefsng Defdbl Defstr Defint Delete DIMDIR ErrorEdit ENDExit Error expressionField FOR-NEXT-STEPGosub GETFor variable=expression to expression Step expression GET I file number ,record numberGoto IF-THEN-ELSEInput LET KillLine Input ListLoad 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 ResumeRUN line numberlstring expression ,F SaveLine number RUN filename 60 END? 5,8,2 TRON, TroffWidth WaitATN ABSFunctions CHR$Cint CVI CVS Csng10 A# = 1.00/3.00 AO/o =EOF DskfOk· FIXInputs HexsINP LEFT$ INTInstr LOC LENLOF LOGOCT$ MID$MKI$ MKS$ MKD$ Peek expression RightsPOS integer RIGHT$ string,integerSIN SGNSpaces 10 a =1SPC integer SPCIf A$ = 2 then Print Correct Else Goto SQRexpressionTAN 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 Level To halt program execution and return to commandTo tab across the line To resume program execution after it is stopped byPage 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 Source Files Generating Boot-Loaded and PROM-Based VersionsBASIC-80 Object Files BASIC-80 Executable FilesGenerating a Boot-Loaded RMX/80 BASIC-80 This option is used to allocate memory. It is 1 if the boot That are not boot loadedSetting 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 Adding BASIC-SO to an Existing RMX/SO Configuration Configuring DFS on an iSBC 80/10Configuration Requirements ISBC SO/10 System ClockPublic 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