Applesoft: Internals--Page Zero Memory Map (1 of 2)



00-02   START   Initialize low RAM memory

03-05   RDYJSR  Jumps to STROUT

06,07   ADRAYI  Address of AYINT subroutine

08,09   ADRGAY  Address of GIVAYF subroutine

0A-0C   USRPOK  Vector for USR() function

0D      CHARAC  String delimiter

0E      ENDCHR  String delimiter

0F      COUNT   General purpose counter

10      DIMFLG  Flag to permit arrays

11      VALTYP  Variable type indicator.  0=numeric, 1=string

12      INTFLG  Variable type indicator.  1=integer, 0=real

13      GARBFL  Flag to signal the need for garbage collection

14      SUBFLG  Flag to permit array variables.

15      INPFLG  Determines if this is INPUT or READ

16      TANSGN  Used for the sign during TAN() function

1A,1B   SHAPE   High-Res shape pointer

1C      HCOLOR1 High-Res running color mask

1D      COUNTH  High-Res counter

26,27   HBAS    High-Res base address pointer

2C      H2

2D      V2

45      ERROV

50,51   LINNUM  16 bit integer work area

53,54   LASTPT  Pointer to last used string temporary

55-5D   TEMPST  Temporary string descriptor storage area

5E,5F   INDEX   General purpose index

60,61   INDEX2  General purpose index

62-66   RES     Multiply or divide result (HO,MOH,MO,LO)

67,68   TEXTAB  Pointer to start of the program text

69,6A   VARTAB  Pointer to start of simple variable space

6B,6C   ARYTAB  Pointer to start of array variable space

6D,6E   STREND  Pointer to end of storage in use

6F,70   FRETOP  Pointer to top of string free space

71,72   FRESPC  Pointer to new string

73,74   MEMSIZ  Pointer to top of memory

75,76   CURLIN  Current line number

77,78   OLDLIN  Old line number, set up by ctrl-C, STOP, or END

79,7A   OLDTXT  Old text pointer

7B,7C   DATLIN  Line number where data for next READ comes from

7D,7E   DATPTR  Pointer to data for next READ

7F,80   INPPTR  Pointer to where input is coming from

81,82   VARNAM  Storage area for a variable's name

83,84   VARPNT  Pointer to a variable in memory

85,86   FORPNT  Variable pointer for FOR and LET

87,88   OPPTR   Pointer to current formula operation in OPTAB

89      OPMASK  Mask created by current operator

8A,8B   DEFPNT  Pointer used in function definition

8C,8D   DSCPNT  Pointer to a string descriptor

8E      TEMPF3  Temporary pointer

8F      FOUR6   Constant for garbage collection

90-92   JMPER   Internal vector

93      TEMPF1  Temporary pointer

94,95   ARRYPT  Pointer into an array

94,95   HIGHDS  Destination of highest element in BLT.

96,97   HIGHTR  Source of highest element to move in BLT.

98      TEMPF2

99,9A   LOWDS   Location of last byte transferred into in BLT.

9B,9C   LOWTR   Last thing to move in BLT.  See BLTU.

9D-9F   DSCTMP  Temporary string descriptor

9D-A2   FAC     Floating point accumulator.

                (EXP,HO,MOH,MO,LO,SGN)





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This information is from the Apple Technical Information Library.



ArticleID: TECHINFO-0000092



19960724 15:55:27.00

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