Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!swrinde!zaphod.mps.ohio-state.edu!sol.ctr.columbia.edu!ira.uka.de!fauern!fauern!csbrod From: csbrod@medusa.informatik.uni-erlangen.de (Claus Brod ) Newsgroups: comp.sys.atari.st.tech Subject: Re: Hard Drive interferring w Mono Monitor. Solution Sought Message-ID: <3202@medusa.informatik.uni-erlangen.de> Date: 31 Oct 90 10:04:08 GMT References: <8905@ncar.ucar.edu> <1990Oct26.104012.15218@agate.berkeley.edu> <38754@ut-emx.uucp> Organization: CSD, University of Erlangen, W-Germany Lines: 27 steveg@com.com (Stephen Harold Goldstein) writes: >I had a similar problem with my Mega 4 and my mono monitor. >Color worked fine, but accessing either of my hard drives >(a Seagate 277N and a Syquest 44meg cart) with my *NEW* >ICD Advantage ST (no plus) adapter would make the mono monitor >APPEAR to lose both horizontal and vertical sync. I played around >with the monitor adjustments and was able to stabilize vertical >hold for both normal and "Weird" mode, but the horizontal display >was still flaked out - seems like there were the right number of >black and white dots per scan line, but they were garbled. Perhaps this has something do to with spikes on the RESET line on the DMA bus. Since RESET is connected to nearly everything inside your ST, those spikes can severely influence the behavior of your computer. Especially the shifter custom chip doesn't like spikes. This might or might not be the explanation of 'weird mode' (still wonder how many colors you could get in this hyper-interlace kind of mode 8-); due to the somewhat unstable design of the DMA bus, there are probably other possible reasons. ---------------------------------------------------------------------- Claus Brod, Am Felsenkeller 2, Things. Take. Time. D-8772 Marktheidenfeld, West Germany (Piet Hein) csbrod@medusa.informatik.uni-erlangen.de ----------------------------------------------------------------------