Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!swrinde!elroy.jpl.nasa.gov!ncar!hsdndev!cmcl2!adm!smoke!gwyn From: gwyn@smoke.brl.mil (Doug Gwyn) Newsgroups: comp.sys.apple2 Subject: Re: It still doesn't work. Is it me? Message-ID: <16111@smoke.brl.mil> Date: 11 May 91 00:27:05 GMT References: Organization: U.S. Army Ballistic Research Laboratory, APG, MD. Lines: 19 In article whitewolf@gnh-starport.cts.com (Tae Song) writes: >|Turn DMA on the APPLE SCSI card OFF and it should work. Leave all the other >|switches on. the transwarp / SCSI combination is most likely your problem >|with DMA on. >I thought the TransWarp GS was DMA compatible? If he is using an OctRAM memory >card he must be using a GS. >You'd only have a peoblem if you're using a the older TWGS, which isn't fully >DMA compatible and need the PALs replaced. We've been over this one before, too. Summarizing: You need the TWGS 2B PAL upgrade for DMA compatibility. You also need the OctoRAM configured with 1MB SIMMs, or else no more than 4 of the 256KB SIMMs. 8 256KB SIMMs is not a DMA-compatible configuration for the OctoRAM. (Technically, 8 1MB SIMMs is also not a DMA-compatible configuration, but the special hackery in Apple's High-Speed SCSI Card firmware to avoid DMA to addresses higher than 4MB will prevent a problem, especially if you set aside the upper 4MB as a RAM disk via the IIGS Control Panel.)