/* System Specific C02 Header File Template */

/* This header contains standardized Constants, *
 * Variables, and Function Calls tailored to a  *
 * a specific platform.                         */

/* System Specific ASCII Key Codes              */
#define DELKEY $7F //Delete/Backspace Key
#define ESCKEY $1B //Escape/Stop Key
#define RTNKEY $0D //Return/Enter Key
#define NULKEY $00 //No Key was Pressed

/* Zero Page Variables used as Pointers         */
char strlo,strhi; //String pointer for String and I/O functions
char dstlo,dsthi; //Secondary string pointer for String functions
char blklo,blkhi; //Block Segment Pointer
char stklo,stkhi; //Stack Pointer

/* Ephemeral Library Variables                  *
 * Available for use in program code, but may   *
 * be obliterated by Function Calls.            *
 * May be Zero Page, but not required           */
char temp0,temp1,temp2,temp3;  //Temporary variables 

/* Static Library Variables                     *
 * Must be preserved between function calls     *
 * May be Zero Page, but not required           */
char blkslo, blkshi; //Block Start Address
char blkelo, blkehi; //Block End Address
char blklen;         //Block Segment Length
char stkslo, stkshi; //Stack Start Address
char stkelo, stkehi; //Stsck End Address
char random;         //Last Result of Pseudo-Random Number Generator
char rdseed;         //System Seed for Pseudo-Random Number Generator 

//System Subroutines
void delchr(); //Delete previous character
char getkey(); //Read ASCII character from Console
char getpos(); //Get Cursor Position
char getsiz(); //Get Screen Size
void newlin(); //Advance cursor to beginning of next line
char polkey(); //Poll Console for character
char putchr(); //Print ASCII character to Console
void prbyte(); //Print Accumulator as Hexadadecimal number
void prhex();  //Print Low Nybble of Accumulator as Hex Digit
char getchr(); //Wait for character from Console
void setpos(); //Set Cursor Position

//System Labels
start:  //Start of Code
exit:   //Return to Operating System