Jon Relay's Apple II Info Archives: Zero Page Addresses

[jonINTERNETrelayCHAT@napaVALLEYnet.CLARInet (Jon Bettencourt)]

$06-$09 - Free Space (Address of Main Menu Routine for Jon Relay's Desktop)
$0A-$0C - JMP to USR() User Function Routine
$18     - First Data Track
$19     - First Data Sector
$1A-$1B - Shape Pointer for DRAW (???)
$1C     - Last COLOR Used
$1D-$1E - Free Space
$20     - Left Margin (0 - 39/79, 0 is default)
$21     - Width (1 - 40/80, 40 is default, 0 crashes Applesoft)
$22     - Top Margin (0 - 23, 0 is default, 19 in graphics mode)
$23     - Bottom Margin (0 - 23, 23 is default)
$24     - Horizontal Cursor Position (0 - 39/79)
$25     - Vertical Cursor Position (0 - 23)
$26-$27 - Address of Byte Containing X,Y (???)
$28-$29 - Base Address of Text Cursor's Position
$2B     - Boot Slot * 16
$2C     - Lo-Res HLIN/VLIN Endpoint
$30     - COLOR Value * 17
$32     - Text Mask ($FF = Normal, $7F = Inverse, $3F = Flashing)
$33     - Prompt Character
$36-$37 - Address of Output Routine
$38-$39 - Address of Input Routine
$50-$51 - Result of the Conversion of the FAC to a 16-Bit Integer
$67-$68 - Address of Beginning of BASIC Program ($0801 is default)
$69-$6A - Address of Beginning of BASIC Variables
$6B-$6C - Address of Beginning of BASIC Arrays
$6D-$6E - Address of End of BASIC Variables
$6F-$70 - Address of End of String Data
$71-$72 - Address to Move String To (???)
$73-$74 - Address of Beginning of String Data
$75-$76 - Current Line Number Being Executed
$77-$78 - Line Number Where END or STOP or BREAK Occurred
$79-$7A - Address of Line Number Being Executed
$7B-$7C - Current Address of DATA
$7D-$7E - Next Address of DATA
$7F-$80 - Address of Input or Data (???)
$81-$82 - Last Used Variable's Name
$83-$84 - Last Used Variable's Address
$9B-$9C - Pointer for $D61A and $F7D9 (???)
$9D-$A3 - Floating Point Accumulator (FAC)
$A5-$AB - Floating Point Argument Register (ARG)
$AF-$B0 - Address of End of BASIC Program
$B1-$B6 - Subroutine to Increase the String Data Pointer
$B7-$BE - Subroutine to Return the Character Pointed to by the String Data
Pointer
$CE-$CF - Free Space
$D4     - Error Code Flag (???)
$D7     - Free Space
$D8     - Error Flag (???)
$DA-$DB - Line Number Where Error Occurred
$DE     - Error Code
$E0-$E1 - Horizontal Coordinate of HPLOT
$E2     - Vertical Coordinate of HPLOT
$E3     - Free Space
$E4     - HCOLOR Value (0=0, 1=42, 2=85, 3=127, 4=128, 5=170, 6=213, 7=255)
$E6     - High Byte of Address of First Byte of Where HGR is Plotted
$E7     - SCALE Value (0 = 256)
$E8-$E9 - Address of Shape Table
$EA     - DRAW/XDRAW Collision Count
$EB-$EF - Free Space
$F1     - SPEED Value (Subtracted From 256)
$F9     - ROT Value
$FA-$FE - Free Space
$FF     - Free Space (Flag Bits for Jon Relay's Desktop)

-- 
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jonrelay@napanet.net                        dimension18.cjb.net
An Apple II fanatic since 1998!     S0.5 LIS+++! Suzy+++! M1987
A Macintosh fanatic since 1996?       OM0.1 OZY++ MIL+++! M1987
An Ozy & Millie fanatic since 2000. MC1.0 CHL+++! TAM+++! M1987
"Remember, if it's not a secure web server, it's an _insecure_
web server!"                                              -- Me

 *_     Syntax Error: an error on a criminal's tax record.
   |    Bad Subscript: a criminal reading a book on a subway.
  ---   Unimplemented Trap: when a bear trap isn't set up 
 |' ,|  properly and thus does not work.
  ---   Overflow: too many ice cubes.      <Can't Restart>

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