ast@cs.vu.nl (Andy Tanenbaum) (06/07/87)
I recently received mail asking whether I would include a disk driver for the hard disk used on the 8 MHz IBM PC-AT in MINIX 1.2. I don't have one of those machines here, so I don't even know what kind of a disk it is. If someone who knows about that disk will post a note saying what controller it uses, that would be nice. If someone would modify at_wini.c or xt_wini.c to use it, that would be even better. I will include it for the benefit of people with 8 MHz AT's if someone else will write it. On the same subject, I would like to include the western digital disk driver in the next release as well. There was a lot of discussion about it earlier, and I sort of lost track of it, but since the discussion died down, I presume a working driver eventually became available. Will someone who has the driver and followed the discussion well enough to know that they have the most recent version send me mail. Then I will ask one of the people replying to send me the driver. (Such a request may generate a lot of transatlantic mail, but at least it will be short mail.) Thanks. Andy Tanenbaum (ast@cs.vu.nl)
boh@cullvax.UUCP (06/11/87)
ast recently posted a request for volunteers to work on modifying at_wini.c for 8Mhz IBM PC/AT's. I have on loan from my employer what I believe to be an 8MHz Model 339 IBM PC/AT. The records which indicate which flavor of AT it really is have been lost for all time. Examination of my motherboard gives no clues as to what crystal my AT is using. There is what appears to be a crystal close to the CPU but I would need a microscope to read the inscriptions. The only other clue is that the NORTON utility SI returns a "Built-in BIOS programs dated Monday, June 10, 1985" and "Computing performance index relative to IBM/PC: 5.7". I also have a 30MByte Hard Drive but I am not sure if this is the original or if it was upgraded from a 20MByte. I am assuming that I have an 8MHz machine because I have had no luck with the MINIX 1.1 at_wini.c. I have been spending a considerable amount of my spare time since receiving MINIX 1.1 trying to get MINIX on my hard disk. I have partitioned my hard disk into two partitions cylinders 0 to 531 for DOS and 532 to 731 for MINIX. The problem is that I can #mkfs /def/hd2 1000 (anything above 1000 usually results in the following error message) and successfully copy certain files out to /dev/hd2 (mounted as /user) but frequently get "Winchester wouldn't reset, drive busy". I have tried various changes to at_wini.c that have been posted on comp.os.minix but none have worked, this is understandable since most fixes have addressed the WD1002 chip set. What puzzles me is that ast has posted that he pulled apart two 6Mhz AT's (which were apparently used to develop and test the AT winchester driver) and found the following chip set; WD1010P1-05 WD1014CL-01 WD1015PL-03 and I have on my machine the following chip set; WD1010A-PC WD1014-CL WD1015-03 NEC D765AC This would lead me to believe that since the chip sets appear to be the same (therefore they use the same control logic) that this is really a timing problem and not a "status register" problem. I am not a professional developer and I have absolutely no experience with developing drivers of any sort. My experience in 'C' is limited but I do know quite a bit about UNIX from a "user's point-of-view". I am an eager learner and I am willing to play whatever part I can in getting not only myself but others who have 8Mhz machines up on their hard disks. ast has mentioned that he will include in MINIX 1.2 any patches to at_wini.c to get us 8Mhz people up and running. If there is anyone willing to help myself and others it would be greatly appreciated. Any hints as to what I might be doing wrong would be greatly appreciated. I thank those individuals who have already made suggestions. I will post any conclusions or final source changes in comp.os.minix after I have tested them on my machine. For those of you who are more experienced than myself in the world of UNIX and development in general thankyou for your openess in discussing technical issues surrounding various "tweaks" made to MINIX. Following this news group is an incredible learning experience, please keep the discussions going. P.S. I purchased the 640K version of MINIX 1.1 so that I could have a larger RAM disk. Could this affect the performance of AT hard drive even though I have recompiled the kernel with at_wini.c? Besides recompiling kernel after changing at_wini.c to wini.c do I need to make any other changes in the operating system in order to get install new driver?
cy@ashtate.UUCP (06/12/87)
Sounds like yours is not 8MHz. My AT Model 339 reports 7.7 from Norton's SI program, and the ROM date is Friday, 11/15/85. --ashtate!cy@seismo.CSS.GOV