koonce@ragu.berkeley.edu (tim koonce) (09/18/88)
Finally got a hard disk controller to put into my Burke & Burke interface, but am having a LOT of problems getting the system to run reasonably. Can anyone help? Here's the hardware setup: A Y-cable with the Disto SCII, B&B hard disk interface with Adaptec 2072 controller, PBJ 2-sp pack, and Speech/Sound cartridge. After I had some problems earlier, I modified the SCII (according to instructions from Tony Distefano) to disable the MEB, which I had suspected was causing problems due to addressing conflicts. I also cut the CTS* line on the B&B interface, and pulled it high through a 1k resistor, to prevent ROM conflicts. I then reassembled everything and re-formatted the hard disk. Here's the symptoms. After successfully formatting the hard disk, I've been trying to copy some stuff over to it. Periodically, attempts to read or write the hard disk cause the program to hang. Usually, this happens in the shell when I try to execute something from the hard disk. As an example, to test it, I copied 'ar' and a large archive over to the hard disk, which seemed to work. I then changed my execution and data directories to the hard disk. Typing 'ar' at the shell prompt simply hung. From another window, mdir did not show 'ar' in the module directory, but 'procs' did show 'ar' executing, with zero memory. Attempts to reference the hard disk from the second window also hung, and, since I only had two windows open, I had to reboot. These hangs seem to be infrequent at first, but occur more often once I actually get some stuff onto the disk. Such hangs also seem to occur every time I try to execute a program of any length from the hard disk. Short utilities, such as 'dmode', seem to load and execute fine. Longer utilities fail consistently. This also seems to happen whenever I simply 'load' one of these longer utilities (it appears in the 'procs' listing, but not in the 'mdir' listing). First question: Under what conditions will the hard disk driver simply stop? I've noticed that the Tandy floppy driver will simply hang if there is no disk available. Will the B&B driver act similarly if the hard disk fails to respond? What might cause the hard disk to not respond? The only possible hardware problem that might remain (I hope) is that I am (due to some incorrect information I got when I first got the drive) using an RLL controller with an MFM drive. For obvious reasons, this might take a little while to correct. (Anyone want to swap an Adaptec 2072 for a comparable MFM controller?) Does anyone know of any reason why this might cause such serious problems? (I would expect the occasional CRC error or bad sector, but a complete hang is a little severe.) Any help is appreciated, Tim Koonce koonce@math.berkeley.edu ...!ucbvax!math!koonce
knudsen@ihlpl.ATT.COM (Knudsen) (09/19/88)
I had no trouble to speak of with my B&B. Sounds like you have at least 3 packs plugged into your Y-cable. From what I've heard, and my own experiences, I wouldn't get within 3 blocks of your house when you're using that setup. Yes, MPIs are hard to find and some folks hate 'em, but Y-cables just won't work reliably. You'd think they would, with the improved bus drive in the III, but not in my experience. Good luck, mike k
pete@wlbr.EATON.COM (Pete Lyall) (09/20/88)
(Tim Koonce talks about the system hanging when hard disk interface is
used):
Question: is the hard disk driver (and descriptor) part of your
bootfile? If not, and you have loaded it, make *sure* you INIZ the
hard drive before doing CHX, CHD or other related stuff. Cannot tell
you why, but doing it without INIZ'ing can gum up the works. If it
*is* part of your bootfile, try rearranging the bootfile.
Pete
--
Pete Lyall (OS9 Users Group VP)| DELPHI: OS9UGVP | Eaton Corp.(818)-706-5693
Compuserve: 76703,4230 (OS9 Sysop) OS9 (home): (805)-985-0632 (24hr./1200 baud)
Internet: pete@wlbr.eaton.com UUCP: {hacgate,jplgodo,voder}!wlbr!pete burke_vern@dneast.dec.com (WHY BE NORMAL?) (09/20/88)
you probably won't have much success trying to run a drive designed for mfm with an rll controller.some drives can stand it for a while,but eventually it ends up ruining the interface cicuitry on the drive.also,some the disk used in mfm drives can't pack the info as tight,hence the data errors. either get an rll drive to go with the controller,or an mfm controller to go with the drive! vern
knudsen@ihlpl.ATT.COM (Knudsen) (09/21/88)
Since Pete reminded us to INIZ devices that aren't in the boot, I thought I'd mention that in my experience, INIZ is more likely to do something useful if you OMIT the '/' from the device name, ie, say INIZ H0 but not INIZ /H0. As Pete would say, I don't know why. I guess INIZ wants module names (like LINK, UNLINK, DEBUG do), not path names. Makes sense, but we phone-co OS-bred types always want to put slashes on device names ;-). BTW, I did a lot of hard drive work with a hand-loaded (non booted) driver-descriptor pair and had absolutely no trouble with it other than wasting almost 8K of precious system memory. (That's 16K if you forget to MERGE the .dd and .dr). It's a shame that an early rumor got started that you can't load .dd's and .dr's in Level II. It just costs you more memory.