Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!think.com!mintaka!bloom-beacon!eru!hagbard!sunic!isgate!krafla!adamd From: adamd@rhi.hi.is (Adam David) Newsgroups: comp.sys.atari.st.tech Subject: Re: 1.44 MB project Keywords: Floppy Disk Message-ID: <3242@krafla.rhi.hi.is> Date: 13 Jun 91 08:44:32 GMT References: <5827@wucc.waseda.ac.jp> <1991Jun11.150348.22250@informatik.uni-erlangen.de> <5832@wucc.waseda.ac.jp> Organization: University of Iceland Lines: 53 In <5832@wucc.waseda.ac.jp> ytsuji@wucc.waseda.ac.jp (Y.Tsuji) writes: >[...] csbrod@immd4.informatik.uni-erlangen.de (Claus Brod) writes: >> ytsuji@wucc.waseda.ac.jp (Y.Tsuji) writes: >> >I posted an appeal for beta testers of a 1.44 MB drive hack six weeks >> >ago and have received 23 responses. I responded back then and have exchanged ideas with Y.Tsuji. His suggestion for eliminating the need for changing the step rates is simple yet effective. I am surprised that for nearly 2 years (or longer?), people have struggled with fixing software drivers or they accept using a slow step rate for DD disks. There are various other hints and tips which don't seem to be mentioned in the ST-Computer 1/90 article. >> The problem with your appeal is that we all already have HD disks connected >> to our STs 8-) - at least in Germany. I was one of the developpers of this >> hack; our article appeared in 'ST-Computer' 1/90. Commercial HD disk >> adapters are available at every corner, and the principles used are >> published. This is probably why you got such a weak response. Germany is the most active area for Atari computers, but there are others. Not everyone can read German, and many users never see the magazines. The project in the magazine article seems to handle only one HD floppy drive. Obviously it works, but it didn't suit my purposes. I had a look at an HD adapter module from 'Hard and Soft' in Germany. It also could only handle one HD drive, but at least it generates the 16 MHz clock signal on board and divides it to 8 MHz for DD disks. I think this was a different product from the CompuWare HD-Modul. It doesn't buffer the side-select signal and there is no provision for fixing the media-change problem on those floppy drives which are smart enough to keep track of disk changes. >What I have known is a product known as HD-Module [...] >If that was ever as good as it claims, I hadn't had any reason to make my own. It was the same for me. I have just finished building my own circuit design on wirewrap holeboard (the first attempt was on stripboard which caused too much interference in HD-mode). Public thanks to Y.Tsuji for the correct handling of steprates in hardware, and other invaluable help. It is only right that manufacturers and users of commercial hardware, and hobbyists / hardware hackers are aware of the limitations (some of them serious) in the equipment. I'm glad I didn't have to buy a WD1772 accelerator module, only to find I couldn't use it anyway without redesigning from scratch. I'm sure others have been less fortunate and have to put up with what they bought because they had incomplete information when they bought it. Anyone who wants to build an HD floppy control board for their ST should definitely benefit from reading the 1.44 MB project docs by Y.Tsuji. -- Adam David. (adamd@rhi.hi.is)