Intel 9800758-02 manual L4! = Csng l4, YI,1

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BASIC-SO

Language Elements

Converting Data

It is sometimes useful to convert one type of data into another. BASIC-SO suppo. I..., these conversions with the HEX$, OCT$, CHR$, STR$, VAL, CVD, CVI, CVS, CDBL, CSNG, CINT, MKS$, MKD$, and MKI$ functions.

The HEX$ and OCT$ functions return a string of hexadecimal and octal digits, respectively, that represent the numeric argument. The STR$ function returns a string of decimal digits that represent the decimal value of the argument. The VAL function returns the numeric value of the string argument, if the string is a number.

CHR$ returns the ASCII equivalent of an integer argument, between 0 and 255.

The CVI, CVS, and CVD functions convert a given string into integer, single- preci- sion floating-point, or double-precision floating-point numeric values, respectively. These functions are used to retrieve numeric values from the input/output buffer when doing random disk 110.

The MKI$, MKS$, and MKD$ functions convert integer, single-precision floating- point, and double-precision floating-point numeric values, respectively, into a string. These functions are used to store humeric values in the input/output buffer when doing random disk 110.

You can convert a numeric variable (integer, single-precision floating-point, or double-precision floating-point) to any of these types by using the variable in an ex- pression with the CINT, CDBL, or CSNG functions:

A# = CDSl (A%)

l4! = CSNG (l4)

VAR5 = CINT (VAR5)

Array Variables

An array is a group of variables identified by the same name, specified by subscripts that define their position in the array. An array variable can have as many dimen- sions as will fit on a single line. An array variable is specified by following a variable name with as many subscripts as there are dimensions. A subscript must be an in- teger value, and enclosed within parentheses or square brackets. If there is more than one subscript, separate them with a comma. Expressions can be used to specify subscripts; they are rounded to integer form. Here are some array variables:

X(10)

R1 (5,4)

Y(I,1)

SA(I + 3,X(10))

BASIC-SO normally indexes arrays from zero; that is; the first element in an array is defined as O. To start arrays at one in BASIC-SO, enter the instruction OPTION BASE 1 in your program before you dimension or reference any arrays.

The DIM statement allocates array space and specifies the maximum allowable subscript for a given dimension. If an array variable is referenced before it has been formally dimensioned, BASIC-SO allocates an index of 10 for each dimension. Some examples of the DIM statement:

DIM X(15)

DIM R1(12,8)

DIM K(17,24)

An attempt to specify an array variable whose subscripts are larger than the dimen- sioned value, or which exceed 10 in the default mode, causes a SUBSCRIPT OUT OF RANGE error message~

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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 ConstantsSingle-Precision Floating-Point Constants Octal Integer ConstantsDouble-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 LSyntax Error Messages BASIC-80 Error MessagesOverflow, Underflow, and Divide-by-Zero 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 FileDefining a Random 1/0 Field-FIELD BuffersField #3, 20 AS N$ 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 expressionInput IF-THEN-ELSEGoto List KillLET Line InputLoad LSET, RsetNEW Merge9 16 NextOn ... Goto On ... GosubOpen OUT Option BasePoke Print Print UsingString Fields 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 ABSCint CHR$Functions AO/o = CsngCVI CVS 10 A# = 1.00/3.00EOF DskfOk· FIXINP HexsInputs Instr INTLEFT$ LOG LENLOC LOFMKI$ MKS$ MKD$ MID$OCT$ RIGHT$ string,integer RightsPeek expression POS integer10 a =1 SGNSIN SpacesSQRexpression SPCSPC integer If A$ = 2 then Print Correct Else GotoTAB expression STR$ expressionTAN 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
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