; ---------------------------------------------------------------------------
; Zero page, Commodore stuff
-DEVNUM := $D4 ; Device number
-
-
+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 := $E840
VIA_PRB := $E840
VIA_PRA := $E841
-VIA_DDRB := $E842
-VIA_DDRA := $E843
+VIA_DDRB := $E842
+VIA_DDRA := $E843