Path: utzoo!attcan!uunet!lll-winken!uwm.edu!wuarchive!zaphod.mps.ohio-state.edu!ncar!boulder!stan!dancer!imp From: imp@dancer.Solbourne.COM (Warner Losh) Newsgroups: comp.sys.dec.micro Subject: Floppies and the Rainbow. Message-ID: <1990Jul12.174636.15655@Solbourne.COM> Date: 12 Jul 90 17:46:36 GMT Sender: news@Solbourne.COM Organization: Solbourne Computer, Inc. Lines: 44 I just put a 3.5" flopply in my Rainbow. Here are some of the things that I noticed: 1) If you just plug it in right out of the box, and format it, then you have a 3.5" RX-50. You can boot off of it and put files on it. One side 400K. 2) The rainbow really wants to have BOTH an A and a B drive in order to boot w/o errors. It appears to be safe to ignore the error about "Drive A" not repsonding when the 3.5" guy is setup as drive "B". 3) The second connector uses the SELECT 0 edge for drive C and SELECT 1 for drive D edge. So there is no need for a "special" cable for drives here (except that it needs to be longer than the "standard" RX-50 cable). 4) It appears to be possible to specify the head to use for the drive, but this will require some driver hacking to make it useful, so it may take me a while. 5) DOS supports a head number for the floppies through IOCTL and INT 65. Please note that this is the low density 720K drive that I'm doing this with. The 1.44M floppy doesn't want to work in my Rainbow out of the box, so I'm not sure what to do with it. Cables are just 34 pin ribbon cable straight through. You can get the parts at Radio Shack for about $10.00. This doesn't include shielding, however. I don't know why exactly it is needed, but the RX50 cable that I have has lots of it on the cable. You may need to figure out how to get more power drops inside the Rainbow. I haven't done this yey, but it looks easy. Now that SS is gone, is there any interest in a PD double sided driver for the Rainbow? Warner -- Warner Losh imp@Solbourne.COM Boycott Lotus. #include