; ; PET generic definitions. ; ; --------------------------------------------------------------------------- ; Zero page, Commodore stuff VARTAB := $2A ; Pointer to start of BASIC variables MEMSIZE := $34 ; Size of memory installed TXTPTR := $77 ; Pointer into BASIC source code TIME := $8D ; 60HZ clock KEY_COUNT := $9E ; Number of keys in input buffer RVS := $9F ; Reverse flag CURS_FLAG := $A7 ; 1 = cursor off CURS_BLINK := $A8 ; Blink counter CURS_CHAR := $A9 ; Character under the cursor CURS_STATE := $AA ; Cursor blink state SCREEN_PTR := $C4 ; Pointer to current char in text screen CURS_X := $C6 ; Cursor column FNLEN := $D1 ; Length of filename LFN := $D2 ; Current Logical File Number SECADR := $D3 ; Secondary address DEVNUM := $D4 ; Device number SCR_LINELEN := $D5 ; Screen line length CURS_Y := $D8 ; Cursor row FNADR := $DA ; Pointer to file name BASIC_BUF := $200 ; Location of command-line BASIC_BUF_LEN = 81 ; Maximum length of command-line KEY_BUF := $26F ; Keyboard buffer ;---------------------------------------------------------------------------- ; PET ROM type detection PET_DETECT := $FFFB PET_2000 = $CA PET_3000 = $FC PET_4000 = $FD ;---------------------------------------------------------------------------- ; Vector and other locations IRQVec := $0090 BRKVec := $0092 NMIVec := $0094 ; --------------------------------------------------------------------------- ; I/O: 6522 VIA2 VIA := $E840 VIA_PRB := $E840 VIA_PRA := $E841 VIA_DDRB := $E842 VIA_DDRA := $E843