Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!mnetor!uunet!husc6!mit-eddie!ll-xn!ames!sdcsvax!ucsdhub!hp-sdd!ncr-sd!crash!gryphon!jdow From: jdow@gryphon.CTS.COM (Joanne Dow) Newsgroups: comp.sys.amiga Subject: Re: PALs,jumpers and expansion on the Amiga 1000. Message-ID: <1504@gryphon.CTS.COM> Date: Fri, 11-Sep-87 15:46:08 EDT Article-I.D.: gryphon.1504 Posted: Fri Sep 11 15:46:08 1987 Date-Received: Sun, 13-Sep-87 02:24:52 EDT References: <8709010613.AA05631@cogsci.berkeley.edu> <1367@ihlpm.ATT.COM> <2141@tekigm2.TEK.COM> Reply-To: jdow@gryphon.CTS.COM (Joanne Dow) Organization: Wizardess Designs Lines: 57 Keywords: Two on the Bus In article <2141@tekigm2.TEK.COM> phils@tekigm2.UUCP (Philip E Staub) writes: >In article <1367@ihlpm.ATT.COM> nevets@ihlpm.ATT.COM (Steven R Ringwood) writes: >>In the end I used wire-wrap wire, a solding iron, and an old alligator clip. > ^^^^^^^^^^^^^^ >> >... >> >>Did it work, for me YES. >> >>Before making this change i could not get by 2Meg Starboard II and >>Supra 30Meg harddisk to work together. >> >>After the 'fix', they both work but only if the Supra is first on the >>bus for some reason. >> >... >> >>Steven Ringwood >>ihnp4!ihlpm!nevets >This *may* >clear up your position dependency, although I rather suspect that the real >reason is that the disk controller's circuitry is more susceptible to the >degraded signal timings available at the end of the bus. Not likely. (Decided to follow up here as this is of general interest.) I have three expansions working just fine on my Amiga with no PAL fix. (I'm using a CMOS 68000 these days.) Back in the days I only had SB2 and Supra Drive (SD) things worked with them in either order. Then I received a new driver from Supra. This new driver insisted that my SB2 be located outboard of the SD. There is a comment elsewhere that this is tied in with the presence of the MFM, Multi Function Module. This I have not confirmed. This position sensitivity continues today after I added the Spirit Technoligies 1.5 meg ram and clock board. (Which is working just peachy for me.) (An aside re clock modules... Learn how to program it at the hardware level - call Spirit perhaps. Then build a program that records the last time the clock was set, an error parts/million, and an update interval. Have this program run in the background waking up every interval to correct the clock by the error percent. Heck - Amigas are MT machines. Fake it. Clock crystals are designed for wrist temperatures. They have vicious temperature dependancy curves. If your unit runs at an unusual temp then things'll be strange...) Anyway - it seems the problem is either in the SD or the SB2. Since the SB2 worked fine until the new SD software arrived I suspect the SD has a subtle software glitch like an absolute address in I/O space. -- <@_@> BIX:jdow INTERNET:jdow@gryphon.CTS.COM UUCP:{akgua, hplabs!hp-sdd, sdcsvax, ihnp4, nosc}!crash!gryphon!jdow Remember - A bird in the hand often leaves a sticky deposit. Perhaps it was better you left it in the bush with the other one.