Pascalated ZX BASIC Demo #23 - Space Invader

Code:
' PROGRAM Space Invader

' (c) ZarSoft 2022 Pascalated BASIC

' (c) ZarSoft 2023 Pascalated Boriel ZX BASIC

' Written by Ze Oliveira

' Pascalated Sinclair BASIC (c) 1987 by ZarSoft

' Pascalated BASIC Converter (c) 2021 by Zarsoft

' Pascalated Boriel (c) 2023 by ZarSoft

' ZX BASIC Compiler (c) 2008 by Boriel



#include <input.bas>  ' number = VAL INPUT(12)

#include <screen.bas> ' SCREEN$ function

#include <attr.bas>   ' ATTR function



'--- Pascalated Boriel ---

#define PROGRAM   REM

#define BEGIN    REM

'#define CONST     CONST

#define VAR       DIM

#define INTEGER   LONG

#define REAL      FLOAT

#define CHAR      STRING ' UBYTE is type integer

'#define STRING    STRING

#define BOOLEAN   UBYTE

#define TYPE      AS

'#define WHILE    WHILE

#define REPEAT    DO

#define UNTIL     LOOP UNTIL

#define PROCEDURE  SUB

CONST   TRUE      TYPE BOOLEAN = 1 

CONST   FALSE     TYPE BOOLEAN = 0 



PROGRAM SpaceInvader



' CONSTant declarations

REM CONSTant declarations

CONST black = 0

CONST blue = 1

CONST red = 2

CONST magenta = 3

CONST green = 4

CONST cyan = 5

CONST yellow = 6

CONST white = 7

CONST ZXscreen = 22528

CONST GameScreen = ZXscreen+4+4*32



' VAR - Global variables

VAR INKoff TYPE INTEGER = blue

VAR INKon TYPE INTEGER= cyan

VAR LEDoff TYPE INTEGER = INKoff+64

VAR LEDon TYPE INTEGER = INKon+64

VAR VIDEO(8,6) TYPE INTEGER ' video memory

VAR ADDR(8,6) TYPE INTEGER ' video address

VAR score1 TYPE INTEGER 

VAR score2 TYPE INTEGER

VAR score3 TYPE INTEGER

VAR PlayerLin TYPE INTEGER

VAR PlayerCol TYPE INTEGER

VAR MissileLin TYPE INTEGER

VAR MissileCol TYPE INTEGER

VAR BombLin TYPE INTEGER

VAR BombCol TYPE INTEGER

VAR MothershipLin TYPE INTEGER

VAR MothershipCol TYPE INTEGER

VAR MothershipInc TYPE INTEGER

VAR Enemies TYPE INTEGER

VAR ScrollState TYPE INTEGER

VAR ScrollLin TYPE INTEGER

VAR ScrollCol TYPE INTEGER

VAR GameOver TYPE BOOLEAN

' VAR Scroll TYPE INTEGER = VAL ("Scroll"+STR$ ScrollState)

VAR k$ TYPE CHAR 

VAR Period TYPE INTEGER = 16



'--- KEYBOARD BUFFER ---



VAR BUFFER$ TYPE STRING = ""

VAR LASTKEY$ TYPE STRING = ""



PROCEDURE ScanKey

VAR key$ TYPE STRING = INKEY$ + "#"

IF key$(0) <> LASTKEY$  

  LASTKEY$ = key(0)

  LET BUFFER$ = BUFFER$+key$(0)

ENDIF

END PROCEDURE



FUNCTION GetKey$ TYPE STRING

VAR result$ TYPE STRING

VAR l TYPE INTEGER

LET l = LEN BUFFER$

IF l = 0

  LET result$ = CHR 0

ELSEIF l = 1

  LET result$ = BUFFER$(0)

  BUFFER$ = ""

ELSE

  LET result$ = BUFFER$(0)

  BUFFER$ = BUFFER$( 1 TO )

ENDIF

RETURN result$

END FUNCTION



FUNCTION LastKey$ TYPE STRING

RETURN LASTKEY$

END FUNCTION



'------------------------



VAR Clock,Clock0 TYPE INTEGER



PROCEDURE WaitClock

VAR elapsed TYPE INTEGER

REPEAT

  ScanKey

  LET Clock = PEEK 23672

  LET elapsed = Clock-Clock0

  IF elapsed<0 THEN LET elapsed = elapsed+256

UNTIL elapsed >= Period

LET Clock0 = Clock0 + Period: IF Clock0 > 255 THEN LET Clock0 = Clock0 - 256

REM PRINT AT 0,0;INK 2;elapsed;"  ";

END PROCEDURE



'------------------------



PROCEDURE InitADDR

VAR l,c TYPE INTEGER

FOR l=1 TO 8

  FOR c=1 TO 6

    ADDR(l,c) = GameScreen+l*64+c*3

    ' POKE ADDR(l,c),18

  NEXT c

NEXT l

END PROCEDURE



PROCEDURE ShipOFF (l TYPE INTEGER,c TYPE INTEGER)

VAR addr TYPE INTEGER

VIDEO(l,c) = 0

addr = ADDR(l,c)

POKE addr,LEDoff: POKE addr+1,LEDoff: POKE addr+2,LEDoff

END PROCEDURE



PROCEDURE ShipON (l TYPE INTEGER,c TYPE INTEGER)

VAR addr TYPE INTEGER

IF VIDEO(l,c) = 0 THEN VIDEO(l,c) = 1 ' do not change shield value

addr = ADDR(l,c)

POKE addr,LEDon: POKE addr+1,LEDon: POKE addr+2,LEDon

END PROCEDURE



PROCEDURE FireOFF (l TYPE INTEGER,c TYPE INTEGER)

VAR addr TYPE INTEGER

addr = ADDR(l,c)

IF VIDEO(l,c) = 0 THEN POKE addr+1,LEDoff

END PROCEDURE



PROCEDURE FireON (l TYPE INTEGER,c TYPE INTEGER)

VAR addr TYPE INTEGER

addr = ADDR(l,c)

IF VIDEO(l,c) = 0 THEN POKE addr+1,LEDon

END PROCEDURE



'------------------------



'------------------------



PROCEDURE ChangeColors

VAR l,c TYPE INTEGER

VAR oldOFF,oldON TYPE INTEGER

oldOFF = LEDoff

oldON = LEDon

INKoff = (black+blue)-INKoff

INKon = (red+cyan)-INKon

LEDoff = INKoff+64

LEDon = INKon+64

' update colors on screen

FOR l=2 TO 4 

  FOR c=7 TO 24

    IF ATTR(l,c) = oldOFF THEN PRINT AT l,c;OVER 1;BRIGHT 1;PAPER 8;INK LEDoff;" ";

    IF ATTR(l,c) = oldON THEN PRINT AT l,c;OVER 1;BRIGHT 1;PAPER 8;INK LEDon;" ";

  NEXT c

NEXT l

FOR l=6 TO 20 STEP 2

  FOR c=7 TO 24

    IF ATTR(l,c) = oldOFF THEN PRINT AT l,c;OVER 1;BRIGHT 1;PAPER 8;INK LEDoff;" ";

    IF ATTR(l,c) = oldON THEN PRINT AT l,c;OVER 1;BRIGHT 1;PAPER 8;INK LEDon;" ";

  NEXT c

NEXT l

END PROCEDURE



'------------------------



PROCEDURE ShowScore

IF score1 > 9 THEN LET score1 = score1-10: LET score2 = score2 + 1: IF score2 > 9 THEN LET score2 = score2-10: LET score3 = score3 + 1: IF score3 > 9 THEN LET score3 = score3-10

ShowDigit(1,score1)

ShowDigit(2,score2)

ShowDigit(3,score3)

END PROCEDURE



'------------------------



PROCEDURE NewWave

' Period for game speed

LET Period = Period-1: IF Period < 8 THEN LET Period = 8

' Enemies

LET VIDEO(2,1) = 1: LET VIDEO(2,2) = 1: LET VIDEO(2,3) = 1: LET VIDEO(2,4) = 1

LET VIDEO(3,1) = 1: LET VIDEO(3,2) = 1: LET VIDEO(3,3) = 1: LET VIDEO(3,4) = 1

LET Enemies = 8

' bombs and missiles 

LET BombLin = 0

LET BombCol = 0

LET MissileLin = 0

LET MissileCol = 0

' Scroll

LET ScrollState = 1

LET ScrollLin = 6

LET ScrollCol = 6

' refresh screen

FOR l=1 TO 8

  FOR c=1 TO 6

    IF VIDEO(l,c) = 0 

      ShipOFF(l,c)

    ELSE

      ShipON(l,c)

    ENDIF

  NEXT c

NEXT l

END PROCEDURE



'------------------------



PROCEDURE MoveLeft

VAR i TYPE INTEGER

IF PlayerCol > 1 

  ShipOFF(PlayerLin,PlayerCol)

  LET PlayerCol = PlayerCol - 1

  ShipON(PlayerLin,PlayerCol)

  BEEP .01,5

ENDIF

END PROCEDURE



PROCEDURE MoveRight

VAR i TYPE INTEGER

IF PlayerCol < 6

  ShipOFF(PlayerLin,PlayerCol)

  LET PlayerCol = PlayerCol + 1

  ShipON(PlayerLin,PlayerCol)

  BEEP .01,5

ENDIF

END PROCEDURE



PROCEDURE MissileFire

IF MissileLin = 0 

  IF VIDEO(7,PlayerCol) = 0  ' freeway

    LET MissileLin = 7

    LET MissileCol = PlayerCol

    FireON(MissileLin,MissileCol)

    BEEP .1,5

  ENDIF

ENDIF

END PROCEDURE



PROCEDURE MissileGo

FireOFF(MissileLin,MissileCol)

LET MissileLin = MissileLin-1

IF  MissileLin >= 1 ' free way

  IF VIDEO(MissileLin,MissileCol) = 0

    FireON(MissileLin,MissileCol)

  ELSE

    IF MissileLin = 1 ' hit on mothership

      ShipOFF(MissileLin,MissileCol): LET MothershipCol = 0

      LET score1 = score1 + 5: ShowScore

      LET MissileLin = 0

      BEEP .01,0: BEEP .01,10: BEEP .01,20: BEEP .01,30

    ELSE ' hit on ship

      ShipOFF(MissileLin,MissileCol) 

      LET Enemies = Enemies - 1: LET score1 = score1 + 2: ShowScore

      LET MissileLin = 0

      BEEP .01,0: BEEP .01,10: BEEP .01,20: BEEP .01,30 

      IF Enemies = 0 THEN NewWave: FOR n=0 TO 30: BEEP .01,n: NEXT n

    ENDIF  

  ENDIF

ENDIF

END PROCEDURE



PROCEDURE BombDrop

LET BombLin = 6

LET BombCol = 1+INT(RND*6)

WHILE VIDEO(BombLin,BombCol) = 0 AND BombLin >= 1

  LET BombLin = BombLin-1

END WHILE

IF BombLin = 1 

  LET BombLin = BombLin+1

  FireON(BombLin,BombCol)

ENDIF

END PROCEDURE



PROCEDURE BombGo

FireOFF(BombLin,BombCol)

LET BombLin = BombLin+1

IF BombLin = 9 

  REM ground zero

  LET BombLin = 0

ELSEIF VIDEO(BombLin,BombCol) = 0 ' free way

  FireON(BombLin,BombCol)

ELSEIF BombLin = 7 ' hit shield

  LET VIDEO(7,BombCol) = VIDEO(7,BombCol)-1: IF VIDEO(7,BombCol) = 0 THEN ShipOFF(7,BombCol): BEEP .2,30

  LET BombLin = 0

ELSEIF BombLin = 8 ' hit defender

  ShipOFF(PlayerLin,PlayerCol)

  LET BombLin = 0

  BEEP .2,5: BEEP .2,7: BEEP .2,0: BEEP .4,0

  LET GameOver = TRUE

ENDIF

END PROCEDURE



PROCEDURE MothershipStart

VAR i TYPE INTEGER

LET MothershipInc = -MothershipInc

LET MothershipCol = 1+5*(MothershipInc = -1)

ShipON(MothershipLin,MothershipCol)

END PROCEDURE



PROCEDURE MothershipGo

ShipOFF(MothershipLin,MothershipCol)

LET MothershipCol = MothershipCol + MothershipInc

IF MothershipCol < 1 OR MothershipCol > 6 

  LET MothershipCol = 0

ELSE

  ShipON(MothershipLin,MothershipCol)

ENDIF

END PROCEDURE



' scroll right

PROCEDURE Scroll1

VAR l TYPE INTEGER

REM shift ship

FOR l = 6 TO 2  STEP -1

  IF VIDEO(l,ScrollCol-1) > 0 THEN ShipON(l,ScrollCol): ShipOFF(l,ScrollCol-1)

NEXT l  

LET ScrollCol = ScrollCol-1

IF ScrollCol = 1 

  IF VIDEO(2,6) + VIDEO(3,6) + VIDEO(4,6) + VIDEO(5,6) + VIDEO(6,6) = 0 

    REM continue scroll right

    LET ScrollState = 1

    LET ScrollCol = 6

  ELSE

    REM goto scroll down (at right corner)

    LET ScrollState = 2

    LET ScrollCol = 6

    IF VIDEO(6,1) + VIDEO(6,2) + VIDEO(6,3) + VIDEO(6,4) + VIDEO(6,5) + VIDEO(6,6) > 0 THEN BEEP .1,5: BEEP .1,7: BEEP .1,0: BEEP .1,0: LET GameOver = TRUE

  ENDIF

ENDIF

END PROCEDURE



' scroll down (at right corner)

PROCEDURE Scroll2

VAR l TYPE INTEGER

REM shift ship

FOR l = 6 TO 3 STEP -1

  IF VIDEO(l-1,ScrollCol) > 0 THEN ShipON(l,ScrollCol): ShipOFF(l-1,ScrollCol)

NEXT l  

LET ScrollCol = ScrollCol-1

IF ScrollCol = 1 ' goto scroll left

  LET ScrollState = 3

  LET ScrollCol = 1

ENDIF

END PROCEDURE



' scroll left

PROCEDURE Scroll3

VAR i TYPE INTEGER

REM shift ship

FOR i = 6 TO 2  STEP -1

  IF VIDEO(i,ScrollCol+1) > 0 THEN ShipON(i,ScrollCol): ShipOFF(i,ScrollCol+1)

NEXT i  

LET ScrollCol = ScrollCol+1

IF ScrollCol = 6 

  IF VIDEO(2,1) + VIDEO(3,1) + VIDEO(4,1) + VIDEO(5,1) + VIDEO(6,1) = 0 

    REM continue scroll left

    LET ScrollState = 3

    LET ScrollCol = 1

  ELSE

    REM goto scroll down (at right corner)

    LET ScrollState = 4

    LET ScrollCol = 1

    IF VIDEO(6,1) + VIDEO(6,2) + VIDEO(6,3) + VIDEO(6,4) + VIDEO(6,5) + VIDEO(6,6) > 0 THEN BEEP .1,5: BEEP .1,7: BEEP .1,0: BEEP .1,0: LET GameOver = TRUE

  ENDIF

ENDIF

END PROCEDURE



' scroll down (at left corner)

PROCEDURE Scroll4

VAR l TYPE INTEGER

REM shift ship

FOR l = 6 TO 3 STEP -1

  IF VIDEO(l-1,ScrollCol) > 0 THEN ShipON(l,ScrollCol): ShipOFF(l-1,ScrollCol)

NEXT l  

LET ScrollCol = ScrollCol+1

IF ScrollCol = 6 ' goto scroll right

  LET ScrollState = 1

  LET ScrollCol = 5

ENDIF

END PROCEDURE



PROCEDURE Scroll

IF ScrollState = 1

  Scroll1

ELSEIF ScrollState = 2

  Scroll2

ELSEIF ScrollState = 3

  Scroll3

ELSEIF ScrollState = 4

  Scroll4

ENDIF  

END PROCEDURE



PROCEDURE ShowDigit0 (col TYPE INTEGER)

PRINT AT 2,col;BRIGHT 1;INK INKon;"\..\..";

PRINT AT 3,col;BRIGHT 1;INK INKon;"\: \ :";

PRINT AT 4,col;BRIGHT 1;INK INKon;"\:.\.:";

END PROCEDURE



PROCEDURE ShowDigit1 (col TYPE INTEGER)

PRINT AT 2,col;BRIGHT 1;INK INKon;"\  \ .";

PRINT AT 3,col;BRIGHT 1;INK INKon;"\  \ :";

PRINT AT 4,col;BRIGHT 1;INK INKon;"\  \ :";

END PROCEDURE



PROCEDURE ShowDigit2 (col TYPE INTEGER)

PRINT AT 2,col;BRIGHT 1;INK INKon;"\..\..";

PRINT AT 3,col;BRIGHT 1;INK INKon;"\..\.:";

PRINT AT 4,col;BRIGHT 1;INK INKon;"\:.\..";

END PROCEDURE



PROCEDURE ShowDigit3 (col TYPE INTEGER)

PRINT AT 2,col;BRIGHT 1;INK INKon;"\..\..";

PRINT AT 3,col;BRIGHT 1;INK INKon;"\..\.:";

PRINT AT 4,col;BRIGHT 1;INK INKon;"\..\.:";

END PROCEDURE



PROCEDURE ShowDigit4 (col TYPE INTEGER)

PRINT AT 2,col;BRIGHT 1;INK INKon;"\. \ .";

PRINT AT 3,col;BRIGHT 1;INK INKon;"\:.\.:";

PRINT AT 4,col;BRIGHT 1;INK INKon;"\  \ :";

END PROCEDURE



PROCEDURE ShowDigit5 (col TYPE INTEGER)

PRINT AT 2,col;BRIGHT 1;INK INKon;"\..\..";

PRINT AT 3,col;BRIGHT 1;INK INKon;"\:.\..";

PRINT AT 4,col;BRIGHT 1;INK INKon;"\..\.:";

END PROCEDURE



PROCEDURE ShowDigit6 (col TYPE INTEGER)

PRINT AT 2,col;BRIGHT 1;INK INKon;"\..\..";

PRINT AT 3,col;BRIGHT 1;INK INKon;"\:.\..";

PRINT AT 4,col;BRIGHT 1;INK INKon;"\:.\.:";

END PROCEDURE



PROCEDURE ShowDigit7 (col TYPE INTEGER)

PRINT AT 2,col;BRIGHT 1;INK INKon;"\..\..";

PRINT AT 3,col;BRIGHT 1;INK INKon;"\  \ :";

PRINT AT 4,col;BRIGHT 1;INK INKon;"\  \ :";

END PROCEDURE



PROCEDURE ShowDigit8 (col TYPE INTEGER)

PRINT AT 2,col;BRIGHT 1;INK INKon;"\..\..";

PRINT AT 3,col;BRIGHT 1;INK INKon;"\:.\.:";

PRINT AT 4,col;BRIGHT 1;INK INKon;"\:.\.:";

END PROCEDURE



PROCEDURE ShowDigit9 (col TYPE INTEGER)

PRINT AT 2,col;BRIGHT 1;INK INKon;"\..\..";

PRINT AT 3,col;BRIGHT 1;INK INKon;"\:.\.:";

PRINT AT 4,col;BRIGHT 1;INK INKon;"\  \ :";

END PROCEDURE



PROCEDURE ShowDigit (ndigit TYPE INTEGER, value TYPE INTEGER)

VAR col TYPE INTEGER

LET col = 12+3*(3-ndigit)

IF value = 0 

  ShowDigit0 (col)

ELSEIF value = 1

  ShowDigit1 (col)

ELSEIF value = 2

  ShowDigit2 (col)

ELSEIF value = 3

  ShowDigit3 (col)

ELSEIF value = 4

  ShowDigit4 (col)

ELSEIF value = 5

  ShowDigit5 (col)

ELSEIF value = 6

  ShowDigit6 (col)

ELSEIF value = 7

  ShowDigit7 (col)

ELSEIF value = 8

  ShowDigit8 (col)

ELSEIF value = 9

  ShowDigit9 (col)

ENDIF  

END PROCEDURE



PROCEDURE ClearScreen

FOR i=2 TO 20

  PRINT AT i,7;OVER 1;BRIGHT 1;INK LEDoff;"                  ";

NEXT i

END PROCEDURE



PROCEDURE Game

VAR active TYPE INTEGER

VAR k$ TYPE STRING

VAR elapsed TYPE INTEGER



REPEAT



  REM process1

  'WaitClock

  REPEAT

    ScanKey

    LET k$ = GetKey$

    IF k$ = "1" THEN MoveLeft

    IF k$ = "2" THEN MoveRight

    IF k$ = "0" THEN MissileFire

    LET Clock = PEEK 23672

    LET elapsed = Clock-Clock0

    IF elapsed<0 THEN LET elapsed = elapsed+256

  UNTIL elapsed >= Period

  LET Clock0 = Clock0 + Period: IF Clock0 > 255 THEN LET Clock0 = Clock0 - 256



  LET active = MothershipCol

  IF NOT active THEN MothershipStart

  IF active THEN MothershipGo

  LET active = BombLin

  'IF Enemies > 3 THEN IF active+RND < ((score3+1.5)*10+score2)/50 THEN BombDrop

  IF NOT active THEN BombDrop

  IF active THEN BombGo

  IF MissileLin THEN MissileGo



  REM process2

  'WaitClock

  REPEAT

    ScanKey

    LET k$ = GetKey$

    IF k$ = "1" THEN MoveLeft

    IF k$ = "2" THEN MoveRight

    IF k$ = "0" THEN MissileFire

    LET Clock = PEEK 23672

    LET elapsed = Clock-Clock0

    IF elapsed<0 THEN LET elapsed = elapsed+256

  UNTIL elapsed >= Period

  LET Clock0 = Clock0 + Period: IF Clock0 > 255 THEN LET Clock0 = Clock0 - 256



  LET active = MothershipCol

  IF NOT active THEN MothershipStart

  IF active THEN MothershipGo

  LET active = BombLin

  'IF Enemies > 3 THEN IF active+RND < ((score3+1.5)*10+score2)/50 THEN BombDrop

  IF NOT active THEN BombDrop

  IF active THEN BombGo

  IF MissileLin THEN MissileGo



  REM process3

  Scroll



UNTIL GameOver

END PROCEDURE



PROCEDURE WaitForPlayer

PRINT AT 23,6;PAPER blue;INK white;" [s]            [c]";

REPEAT

  PAUSE 0

  LET k$ = INKEY$

  IF k$ = "c" THEN ChangeColors

UNTIL k$ = "s"

BEEP .4,5

RANDOMIZE

LET Clock0 = PEEK 23672

PRINT AT 23,6;PAPER blue;INK white;" [1][2]         [0]";

END PROCEDURE



PROCEDURE InitGame

VAR l,c TYPE INTEGER

LET Period = 16+1

' score

LET score1 = 0

LET score2 = 0

LET score3 = 0

ShowScore

' clear screen

FOR l=1 TO 8

  FOR c=1 TO 6

    VIDEO(l,c) = 0

  NEXT c

NEXT l

' Mothership

LET MothershipLin = 1

LET MothershipCol = 0

LET MothershipInc = -1

' defense shield

LET VIDEO(7,2) = 10: LET VIDEO(7,5) = 10

' Player

LET PlayerLin = 8

LET PlayerCol = 1

LET VIDEO(PlayerLin,PlayerCol) = 1

' new wave

NewWave

' extra

LET GameOver = FALSE

END PROCEDURE



PROCEDURE InitScreen

BORDER 1: PAPER 1: INK 7: CLS

PRINT AT 0,8;INK 7;"* SPACE INVADER *";

PAPER 0

FOR i=1 TO 21

  PRINT AT i,6;INK 1;"                    ";

NEXT i

PRINT AT 1,6;INK 7;"\:'\''\''\''\''\''\''\''\''\''\''\''\''\''\''\''\''\''\''\':";

FOR i=2 TO 20

  PRINT AT i,6;INK 7;"\: ";

  PRINT AT i,25;INK 7;"\ :";

NEXT i

PRINT AT 21,6;INK 7;"\:.\..\..\..\..\..\..\..\..\..\..\..\..\..\..\..\..\..\..\.:";

REM PLOT 11*8,176-2*8: DRAW 10*8,0: DRAW 0,-4*8+4: DRAW -10*8,0: DRAW 0,4*8-4

PRINT AT 2,12;INK INKoff;"\..\.. \..\.. \..\..";

PRINT AT 3,12;INK INKoff;"\:.\.: \:.\.: \:.\.:";

PRINT AT 4,12;INK INKoff;"\:.\.: \:.\.: \:.\.:";

PRINT AT 6,7;BRIGHT 1;INK INKoff;"\A\B\C\A\B\C\A\B\C\A\B\C\A\B\C\A\B\C";

FOR i=1 TO 5

  PRINT AT 6+i*2,7;BRIGHT 1;INK INKoff;"\D\E\F\D\E\F\D\E\F\D\E\F\D\E\F\D\E\F";

NEXT i

REM PRINT AT 18,7;INK INKoff;"   \G\H\I      \G\H\I";

REM PRINT AT 19,7;INK INKoff;" \E  \E  \E  \E  \E  \E ";

PRINT AT 18,7;BRIGHT 1;INK INKoff;"\M\E\N\M\E\N\M\E\N\M\E\N\M\E\N\M\E\N";

PRINT AT 20,7;BRIGHT 1;INK INKoff;"\J\K\L\J\K\L\J\K\L\J\K\L\J\K\L\J\K\L";

REM PRINT AT 23,7;INK 7;"12     keys     90";

PRINT AT 23,6;PAPER blue;INK white;" [1][2]         [0]";

END PROCEDURE



PROCEDURE DefineChars

VAR i,n TYPE INTEGER

VAR b$ TYPE STRING

RESTORE ' DataChars

READ b$

REPEAT

  FOR i=0 TO 7

    READ n

    POKE USR b$+i,n

  NEXT i

  READ b$

UNTIL b$ = ""

END PROCEDURE



PROCEDURE DataChars

DATA "A"

DATA BIN 00000000

DATA BIN 00000011

DATA BIN 00000001

DATA BIN 00011111

DATA BIN 00111111

DATA BIN 01111111

DATA BIN 00111111

DATA BIN 00000111

DATA "B"

DATA BIN 00111100

DATA BIN 11111111

DATA BIN 01011010

DATA BIN 11111111

DATA BIN 11111111

DATA BIN 11111111

DATA BIN 11111111

DATA BIN 00111100

DATA "C"

DATA BIN 00000000

DATA BIN 11000000

DATA BIN 10000000

DATA BIN 11111000

DATA BIN 11111100

DATA BIN 11111110

DATA BIN 11111100

DATA BIN 11100000

DATA "D"

DATA BIN 00000010

DATA BIN 00000010

DATA BIN 00000110

DATA BIN 00001111

DATA BIN 00001111

DATA BIN 00011100

DATA BIN 00010000

DATA BIN 00010000

DATA "E"

DATA BIN 00011000

DATA BIN 00111100

DATA BIN 01111110

DATA BIN 11111111

DATA BIN 11111111

DATA BIN 01111110

DATA BIN 00111100

DATA BIN 00011000

DATA "F"

DATA BIN 01000000

DATA BIN 01000000

DATA BIN 01100000

DATA BIN 11110000

DATA BIN 11110000

DATA BIN 00110000

DATA BIN 00010000

DATA BIN 00001000

END PROCEDURE



PROCEDURE DataChars2

DATA "G"

DATA BIN 00000000

DATA BIN 00000000

DATA BIN 00000001

DATA BIN 00000111

DATA BIN 00011111

DATA BIN 01111111

DATA BIN 00000000

DATA BIN 00000000

DATA "H"

DATA BIN 00011000

DATA BIN 01111110

DATA BIN 11111111

DATA BIN 11111111

DATA BIN 11111111

DATA BIN 11111111

DATA BIN 00000000

DATA BIN 00000000

DATA "I"

DATA BIN 00000000

DATA BIN 00000000

DATA BIN 10000000

DATA BIN 11100000

DATA BIN 11111000

DATA BIN 11111110

DATA BIN 00000000

DATA BIN 00000000

DATA "J"

DATA BIN 00000000

DATA BIN 00000000

DATA BIN 00000000

DATA BIN 00011111

DATA BIN 00111111

DATA BIN 01111111

DATA BIN 00111111

DATA BIN 00011110

DATA "K"

DATA BIN 00011000

DATA BIN 01111110

DATA BIN 11111111

DATA BIN 11111111

DATA BIN 11111111

DATA BIN 11111111

DATA BIN 11111111

DATA BIN 00000000

DATA "L"

DATA BIN 00000000

DATA BIN 00000000

DATA BIN 00000000

DATA BIN 11110000

DATA BIN 11111100

DATA BIN 11111110

DATA BIN 11111100

DATA BIN 01111000

DATA "M"

DATA BIN 00000000

DATA BIN 00000000

DATA BIN 00000000

DATA BIN 00001111

DATA BIN 00011111

DATA BIN 00111100

DATA BIN 01111000

DATA BIN 11110000

DATA "N"

DATA BIN 00000000

DATA BIN 00000000

DATA BIN 00000000

DATA BIN 11110000

DATA BIN 11111000

DATA BIN 00111100

DATA BIN 00011110

DATA BIN 00001111

DATA ""

END PROCEDURE



PROCEDURE TellStory

BORDER 1: PAPER 1: INK 7: CLS

PRINT AT 5,0;"In 1980 was launched"

PRINT TAB 0;"the first handheld videogame:"

PRINT TAB 5;""

PRINT TAB 5;INK 6;"SPACE INVADER"

PRINT TAB 5;"  by Entex"

PRINT TAB 5;""

PRINT TAB 5;"Red leds screen"

PRINT TAB 5;"6 x 8 resolution"

PRINT TAB 5;"6 AA batteries"

PRINT TAB 5;""

PRINT TAB 0;"On youtube search:"

PRINT TAB 0;"  Entex Space Invader"

PAUSE 15*50

END PROCEDURE



PROCEDURE MainRoutine

TellStory

DefineChars

InitADDR

InitScreen

WaitForPlayer

InitGame

REPEAT 

  Game

  WaitForPlayer

  ClearScreen

  InitGame

UNTIL FALSE

END PROCEDURE



PROGRAM SpaceInvader

FOR n=0 TO 30: BEEP .01,n: NEXT n

PRINT AT 23,0;"Pascalated Boriel ZX BASIC demo";

PAUSE 3*50

MainRoutine

PRINT AT 21,10;INK 2;"The End"

END PROGRAM