bertfram@ac.dal.ca (11/16/89)
I just bought a copy of Fastback +. When I configured it the other day it informed me that I have an error in my DMA controller chip. I'm not a happy camper. They suggested that I buy a fix from them. This is the first I've heard of this problem, and it hasn't seemed to affect anything in the past. When I try to run Fastback it tells me that it's going to have to run in S-L-O-W mode until I get the problem fixed (yeah, I spent $135 on FASTback so it can work in slow mode!!). Anyway, any and all information on this problem (and possible solutions to it) are very welcome!! BTW, I'm running an XT compatible, at 10/4.7Mhz. Thanks, Brad MORRISON@UG.CS.DAL.CA BERTFRAM@DALAC MORRISON@MOON.SBA.DAL
wb8foz@mthvax.cs.miami.edu (David Lesher) (11/17/89)
> Article <941@ac.dal.ca> From: bertfram@ac.dal.ca
# I just bought a copy of Fastback +. When I configured it the other day
# it informed me that I have an error in my DMA controller chip. I'm not
# a happy camper.
Early DMA controllers, mostly seen on first generation Boca
Raton Boxes, had fatal problems running both DMA channels at the
same time. FastBack+ tests for this flaw. It needs both
channels to be writing to the floppy whilst it is sucking up more
data from the HD. (I understand that before they had this test,
they had all kinds of intermittent data errors they couldn't
figure out...)
The cure is to replace the DMA controller chip with one that
does what it is supposed to. It should be a 2 minute job, but if
the designers soldered it in, or hid it under
something... ......rotsaruck.
I guess I can't see why you are mad at Fastback for attempting to
use your machine in its most efficient mode, and warning you
that the box is not keeping up its end of the deal.
--
A host is a host & from coast to coast...wb8foz@mthvax.cs.miami.edu
no one will talk to a host that's close..............(305) 255-RTFM
Unless the host (that isn't close)......................pob 570-335
is busy, hung or dead....................................33257-0335burkett@csd4.csd.uwm.edu (Edward W Burkett) (11/17/89)
In article <1078@umigw.MIAMI.EDU> wb8foz@Mthvax.Miami.Edu (David Lesher) writes: >> Article <941@ac.dal.ca> From: bertfram@ac.dal.ca > ># I just bought a copy of Fastback +. When I configured it the other day ># it informed me that I have an error in my DMA controller chip. I'm not ># a happy camper. > >The cure is to replace the DMA controller chip with one that >does what it is supposed to. It should be a 2 minute job, but if >the designers soldered it in, or hid it under >something... ......rotsaruck. This is part of an article I posted a while back. A little information about Clones, DMA and FastBack+. I have followed up on a suggestion to contact Fifth Generation Systems, Inc. about DMA chips that do not pass the *fast* FastBack+ test. After talking to a Tech. at FGS, Inc. I learned that there are several clones (Leading Edge is one) and (believe it or not) IBM's that DO NOT have defective DMA chips but rather the architecture of the system limits the access to the DMA chip by a clock or timing problem. I repeat ..... FGS, Inc. said that the problem cannot be cured by replacing the DMA chip (It is not defective). As it turns out, if you have an 8086 or 8088 machine, FGS, Inc. supplies a chip that will fix the timing problem. To install this chip you simply pull the original CPU, insert this 40 pin chip and then piggyback the original CPU onto the new chip. The Tech. assured me that this would fix the DMA problem for any 8086/8088 machine and does not influence the performance of the machine in any other way. Where they get you is that the chip cost $40.00 which includes shipping. Does anybody know anything about this chip? The reason I ask is that FGS, Inc. also suggested replacing the 8088 with a V20. They will sell it to you for $30.00. Well, I can buy one for $7.00!!!! Hmmmm! Maybe the DMA fix chip is also available at a lower cost from a different source. An interesting point was brought out in my discussion with FGS, Inc. Since my original posting, I have gotten MANY replies that the DMA problem was actually a defective DMA chip and that it simply (or not so simply, if it is soldered) had to be replaced. One knowledgable person said that it was due to timing problem machine. This was why I called FGS, Inc. The point is --- investigate a problem like this thoroughly before you spend a LOT of money on someones advice that may not fix the problem---. For those of you who are interested, you do not have to own FastBack to buy this DMA fix chip. They will sell it to anyone. FGS, Inc. address is: Fifth Generation Systems, Inc. 11200 Industriplex Boulevard Baton Rouge, LA 70809 The chips' part number is 132000 Include a check for $40.00 and a return address. If you would like to talk to them, their phone number is 504-291-7283. P.S. (They also said.. DO NOT force a faster speed than FB+ says is ok because you will LOSE data....maybe not the first time....but you will lose data) HOPE THIS HAS BEEN HELPFUL! ******************************************************************************** Ed Burkett University of Wisconsin Department of Biological Sciences ********************************************************************************
kens@hplsla.HP.COM (Ken Snyder) (11/18/89)
Re: Fastback thinks DMA controller's are bad. I've had 2 machines and tried to run Fastback on them. Both (20Mhz 386 and 25Mhz 386) said the DMA was bad and would only run in the slow mode. After being all upset at first, I simply run Fastback in the SLOW dma mode. It takes about a minute to do 1.2M discs (reading or writing). It also doesn't seem to slow at all if you turn on data compression. I use disc caching programs that use the dma channels and they seem to run fine. I think the problem lies in FB's test. Ken
davidsen@crdos1.crd.ge.COM (Wm E Davidsen Jr) (11/18/89)
Two comments: first, the error in the DMA chip is probably real, and second, the speed of the backup is effected more by the i/o speed than cpu. Now if you want to run using compression you will have a performance hit, but if you just want to get the backup written, the slow mode of the cpu probably won't hurt. I've seen this before. -- bill davidsen (davidsen@crdos1.crd.GE.COM -or- uunet!crdgw1!crdos1!davidsen) "The world is filled with fools. They blindly follow their so-called 'reason' in the face of the church and common sense. Any fool can see that the world is flat!" - anon
pechter@ocpt.ccur.com (Bill Pechter <pechter>) (11/19/89)
In article <941@ac.dal.ca>, bertfram@ac.dal.ca writes: > I just bought a copy of Fastback +. When I configured it the other day > it informed me that I have an error in my DMA controller chip. I'm not > a happy camper. They suggested that I buy a fix from them. This is the > first I've heard of this problem, and it hasn't seemed to affect anything > in the past. This is a very common problem in XT's and the Fastback Manual goes into it in depth... There are 2 reasons for the problem: 1. Defective DMA chips (most of these in original PC's) which don't let you do read and write DMA at the same time. 2. Badly built clones that have problems with DMA at high speed. (This is my speculation -- the bad DMA chips should be out of circulation by now. I think this problem is bios related) There are 2 ways to get around this -- run with slow or medium DMA instead of fast DMA, or retry the test at a slower cpu speed with DMA at the fast rate. Fastback Plus at 4.77 MHZ with high DMA beats slow DMA at a 10 meg speed I think (your mileage may vary 8 -} ). Also -- the Fastback Plus tests are sensitive to TSR's. I also improved my DMA rate by changing my refresh rate a bit. Bill (running FB Plus for 2 years on an AT&T 6300 which wouldn't run old Fastback with any kind of reliability...) -- Bill Pechter -- Home - 103 Governors Road, Lakewood, NJ 08701 (201)370-0709 Work -- Concurrent Computer Corp., 2 Crescent Pl, MS 172, Oceanport,NJ 07757 Phone -- (201)870-4780 Usenet . . . rutgers!pedsga!tsdiag!scr1!pechter ** MS-DOS is CP/M on steroids, bigger, bulkier and not much better **
morrison@ug.cs.dal.ca (Brad Morrison) (11/20/89)
I'm NOT mad at Fastback. I was just curious as to whether or not this error message was reliable or not. If it was specific to Fastback + then I'd sooner give up the software than start trying to vaccum-solder my chip out of place (or spend $50+CDN on one of their fixes). Is there anybody out there who's actually used their 'fix'. What kind of adverse effects can I expect (I know, they say none, but hey, they make the thing)?
mrichey@orion.oac.uci.edu (Mike Richey) (11/21/89)
In article <941@ac.dal.ca> bertfram@ac.dal.ca writes: >I just bought a copy of Fastback +. When I configured it the other day >it informed me that I have an error in my DMA controller chip. I'm not >a happy camper. They suggested that I buy a fix from them. This is the >first I've heard of this problem, and it hasn't seemed to affect anything >in the past. When I try to run Fastback it tells me that it's going to >have to run in S-L-O-W mode until I get the problem fixed (yeah, I spent >$135 on FASTback so it can work in slow mode!!). Anyway, any and all >information on this problem (and possible solutions to it) are very >welcome!! > There was once a problem with the 8237 DMA controllers from AMD. The 8237 has four DMA channels available. Most all applications use only a single DMA channel to get data to RAM. What's nice about fastback is that it utilizes two DMA channels to transfer data. One channel to read from the hard disk, and a second to write to the floppy. When the hard disk and diskette drive leds are lit, it's not just because the drives are selected. Well, fastback makes sure that the hardware is capable of performing. If you have a faulty 8237, it will detect it. Which it probably has. Now, I believe that when you install fastback the instuctions say to be sure that your machine is working in the slowest mode available. In your case be sure that you're ooperating the system clock at 4.77 Mhz and not 10 Mhz. The reason it has just showed up now is because you haven't been running any applications that open more than one DMA channel. Well, I don't know that you aren't, but I suspect it. Try re-installing it at 4.77Mhz. Michael S. Richey University of California, Irvine - Network & Telecommunications Services InterNet: mrichey@orion.oac.uci.edu BitNet: MRichey@UCI CompuServe: 71650,3132 Voice: (714) 856-8374
carlson@gateway.mitre.org (Bruce Carlson) (11/21/89)
In article <941@ac.dal.ca> bertfram@ac.dal.ca writes: >I just bought a copy of Fastback +. When I configured it the other day >it informed me that I have an error in my DMA controller chip. I'm not >a happy camper. They suggested that I buy a fix from them. This is the >first I've heard of this problem, and it hasn't seemed to affect anything >MORRISON@UG.CS.DAL.CA >BERTFRAM@DALAC >MORRISON@MOON.SBA.DAL Check to make sure you have specified the type of floppy disk you have, that you have formatted the disk you are using, and that the disk is good; then have Fastback+ do the DMA test again. My AST Premium failed all the DMA tests and when I called the Fastback+ tech support they told me it was probably because I had Windows installed (although not active) or because of some TSR I was using. However, the real problem was that I was using a bad HD 5 1/4 inch disk when I did the DMA test. Since the floppy disk was bad Fastback+ could never successfully use the DMA to back up my hard disk. After I switched to a good floppy disk my PC passed all the DMA tests, up to the highest speed. Your results may vary. Bruce Carlson
zeeff@b-tech.ann-arbor.mi.us (Jon Zeeff) (11/28/89)
In article <3686@orion.cf.uci.edu> mrichey@orion.oac.uci.edu (Mike Richey) writes: >What's nice about fastback is that it utilizes two DMA channels to transfer >data. One channel to read from the hard disk, and a second to write to the >floppy. When the hard disk and diskette drive leds are lit, it's not just Not on an AT. The AT just doesn't have the hardware needed to do dma from the hard disk. -- Jon Zeeff <zeeff@b-tech.ann-arbor.mi.us> Branch Technology <zeeff@b-tech.mi.org>
mlord@bmers58.UUCP (Mark Lord) (11/29/89)
In article <LSGH9V@b-tech.mi.org> zeeff@b-tech.ann-arbor.mi.us (Jon Zeeff) writes: >In article <3686@orion.cf.uci.edu> mrichey@orion.oac.uci.edu (Mike Richey) writes: >>What's nice about fastback is that it utilizes two DMA channels to transfer >>data. One channel to read from the hard disk, and a second to write to the >>floppy. When the hard disk and diskette drive leds are lit, it's not just > >Not on an AT. The AT just doesn't have the hardware needed to do dma >from the hard disk. >-- >Jon Zeeff <zeeff@b-tech.ann-arbor.mi.us> >Branch Technology <zeeff@b-tech.mi.org> Garbage. The IBM PC, XT, and AT models all have DMA hardware specifically for this purpose, as do virtually all clones of any of these computers. And man.. does FastBack ever fly on it! -Mark -- +----------------------------------------+----------------------------+ | Mark S. Lord | Hey, It's only MY opinion. | | ..!utgpu!bnr-vpa!bnr-fos!mlord%bmers58 | Feel free to have your own.| +----------------------------------------+----------------------------+
phil@diablo.amd.com (Phil Ngai) (11/30/89)
In article <566@bmers58.UUCP> mlord@bmers58.UUCP (Mark Lord) writes: |In article <LSGH9V@b-tech.mi.org> zeeff@b-tech.ann-arbor.mi.us (Jon Zeeff) writes: |>Not on an AT. The AT just doesn't have the hardware needed to do dma |>from the hard disk. | |Garbage. | |The IBM PC, XT, and AT models all have DMA hardware |specifically for this purpose, as do virtually all |clones of any of these computers. A little knowlege is a dangerous thing. Yes ATs have DMA hardware. No, ATs don't use DMA on their hard disks. Actually Jon is completely correct in that although ATs do have DMA hardware, it is not hooked up to the hard disks and the statement "AT doesn't have hardware to do DMA from hard disk" is correct. -- Phil Ngai, phil@diablo.amd.com {uunet,decwrl,ucbvax}!amdcad!phil AT&T Unix System V.4: Berkeley Unix for 386 PCs!