Path: utzoo!attcan!uunet!zaphod.mps.ohio-state.edu!sdd.hp.com!ucsd!ucbvax!SIUCVMB.BITNET!ST6934 From: ST6934@SIUCVMB.BITNET Newsgroups: comp.sys.apple2 Subject: Re:safe Zero Page locations Message-ID: <9011130203.AA26300@apple.com> Date: 13 Nov 90 02:02:43 GMT Sender: daemon@ucbvax.BERKELEY.EDU Organization: The Internet Lines: 49 >Date: Mon, 12 Nov 90 18:20:53 GMT >From: Andy Tefft >Subject: safe 0-page addresses >I can never keep track of what 0-page addresses are used by >what program and I need about 7 of them (3 pairs plus one) >that won't be used by applesoft, basic.system, or prodos. >Does anyone have any 0-page maps (with actual meanings >rather than just saying which ones are used)? I only have >monitor locations now. From the Apple II Prodos Technical Reference manual: Appendix A-4:Zero Page- "Figure A-3 is a memory map that shows the locations by the Monitor, Applesoft, the Device Drivers, and the ProDOS MLI. The owner of each location is shown by a letter: M,A,D, or P." Figure A-3. Zero Page Memory Map ____________________________________________________________________________ Use by the Monitor (M), Applesoft (A), Disk Drivers (D), and the ProDOS MLI (P) is shown. Decimal---0 1 2 3 4 5 6 7 8 9 0 11 12 13 14 15 , Hex---$0 $1 $2 $3 $4 $5 $6 $7 $8 $9 $A $B $C $D $E $F ---------------------------------------------------------------------------- 0 $00 | DA DA A A A A A A A A A A 16 $10 | A A A A A A A A A A? A? A? A? A? *M 32 $20 | M M M M M M A?M A?M M M M M A?M A?M M A?M 48 $30 | A?M M A?M A?M M M M M M M PMD PMD A?PMD A?PMD A?PMDA?DM 64 $40 | PMD PMD PMD PMD PMD PMD PMD PM PM PM P P P P PM M 80 $50 | MA MA MA MA MA MA A A A A A A A A A A 96 $60 | A A A A A A A A A A A A A A A A 112 $70 | A A A A A A A A A A A A A A A A 128 $80 | A A A A A A A A A A A A A A A A 144 $90 | A A A A A A A A A A A A A A A A 160 $A0 | A A A A A A A A A A A A A A A A 176 $B0 | A A A A A A A A A A A A A A A A 192 $C0 | A A A A A A A A A A A A A A 208 $D0 | A A A A A A A? A A A A A A A A 224 $E0 | A A A A A A A A A A 240 $F0 | A A A A A A A A A A A? * Byte used in original Apple IIe ROMs, now free. ? Discrepency between ProDOS Technical Reference Manual and the Apple IIe --------------------------------- --------- Technical Reference Manual. Published by Addison-Wesley Publishing Company -------------------------- Copyright 1986 Apple Computer Inc.