Intel 9800758-02 manual Public Variables

Page 105

BASIC-SO

RMX/SO BASIC-SO

Public Variables

An area of RAM as large as possible should be allocated for BASIC-80 work space. The user must supply two routines, BQSMEM and BQEMEM which return the ad- dress of the first byte of BASIC-80 work space in registers Hand L and the last byte of BASIC-80 work space, respectively. The HL register requirement is consistent with PL/M-80 Address procedures.

Example:

PUBLIC BOSMEKM,BOEMEM

CSEG

BOSMEM: LXI H,SMEM

RET

BOEMEM: LXI H,EMEM

RET

DSEG

SMEM: DS 5000

EMEM: DS1

END

A public word variable called BQPRUN must be defined. If the value is non-zero, BASIC-80 will attempt to load and run the BASIC-80 source program at the address specified when BASIC is initiated.

Examples:

 

 

BOPRUN:

PUBLIC

BOPRUN

DW

0 ; no automatic PRUN

or

 

 

BOPRUN:

PUBLIC

BOPRUN

DW

PRUNIT

PRUNIT:

DB

"1 PRINT 'THISWILL PRINT WHEN BASIC

 

 

IS STARTED'"

 

DB

13,10,26 ; CR, LF, Control Z

Three byte public variables define the files available to BASIC. BQUIO should be zero if user-written 110 drivers are included, otherwise it should be one, BQDFS should be equal to zero if DFS is not included in the configuration. If DFS is includ- ed, BQDFS should be equal to the number of DFS files that may be open at once. BQNFIL should be the maximum number of DFS and user files that may be open at one time.

Example:

PUBLIC BOUIO,BODFS,BQNFIL

BOUIO: DB 0

BODFS: DB 6

BONFIL: DB 6

Linking and Locating

RMXBAS.LIB must be added to the list of files given to the LINK program. If a user-written 110 routine is to be used, its object module must also be included.

No special information is needed to locate object code for a system that includes BASIC-80.

F-13

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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 ConstantsOctal Integer Constants Single-Precision Floating-Point ConstantsDouble-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 LBASIC-80 Error Messages Syntax Error MessagesOverflow, Underflow, and Divide-by-Zero 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 FileBuffers Defining a Random 1/0 Field-FIELDField #3, 20 AS N$ 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 numberIF-THEN-ELSE InputGoto LET KillLine Input ListLoad LSET, RsetNEW Merge9 16 NextOn ... Gosub On ... GotoOpen Option Base OUTPoke Print Using PrintString Fields 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 ABSCHR$ CintFunctions CVI CVS Csng10 A# = 1.00/3.00 AO/o =EOF DskfOk· FIXHexs INPInputs INT InstrLEFT$ LOC LENLOF LOGMID$ MKI$ MKS$ MKD$OCT$ Peek expression RightsPOS integer RIGHT$ string,integerSIN SGNSpaces 10 a =1SPC integer SPCIf A$ = 2 then Print Correct Else Goto SQRexpressionSTR$ expression TAB 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 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