💾 Archived View for mirrors.apple2.org.za › archive › apple.cabi.net › FAQs.and.INFO › Accelerators … captured on 2023-01-29 at 07:40:41.
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Path: ns-mx!hobbes.physics.uiowa.edu!moe.ksu.ksu.edu!zaphod.mps.ohio-state.edu!wupost!waikato.ac.nz!comp.vuw.ac.nz!actrix!David.Empson From: David.Empson@actrix.gen.nz (David Empson) Newsgroups: comp.sys.apple2 Subject: Re: Speaking of the Zip... Message-ID: <1991Nov13.121010.18813@actrix.gen.nz> Date: 13 Nov 91 12:10:10 GMT References: <1991Nov11.185126.28247@usenet.ins.cwru.edu> <1991Nov12.135052.365@actrix.gen.nz> Organization: Actrix Information Exchange, Wellington, New Zealand Lines: 42 Comment-To: David.Empson@actrix.gen.nz Sorry, slight error in my previous posting on this subject: the ProDOS-8 QUIT call parameter block has too few zeros in it. The correct program should read: 2000: A9 50 LDA #$50 2002: 8D 5A C0 STA $C05A ; write $50 to $C05A four times to 2005: 8D 5A C0 STA $C05A ; enable access to the ZIP registers 2008: 8D 5A C0 STA $C05A 200B: 8D 5A C0 STA $C05A 200E: 8E 5A C0 STZ $C05A ; write $00 to $C05A to disable the ZIP 2011: 0A ASL 2012: 8D 5A C0 STA $C05A ; write $A0 to stop accessing the ZIP 2015: 20 00 BF JSR $BF00 ; Do a ProDOS QUIT call 2018: 65 $65 2019: 1D 20 $201D 201B: 00 00 BRK $00 201D: 04 00 00 00 00 00 00 Just type in the hex codes on the left, and use the following commands to save it: CREATE SLOW,TSYS BSAVE SLOW,TSYS,A$2000,L$24 To write FAST, simply change one byte: 200F:5B (this changes the STZ $C05A to STZ $C05B) CREATE FAST,TSYS BSAVE FAST,TSYS,A$2000,L$24 Sorry about that. It wouldn't affect the program at all, but might cause compatibility problems with future versions of ProDOS. -- David Empson EMPSON_D@kosmos.wcc.govt.nz David.Empson@bbs.actrix.gen.nz