kgreen@dukeac.UUCP (Kendall B Green) (07/01/89)
I have a Seagate 251 Hard Drive that I want to put into a 80386SX machine. I would like to use an RLL controller to increase the capacity and decrease the access time. From discussions here several months ago it seemed that the consensus was that it is possible to use an RLL controller with this drive. Has anyone had experience with this combination for six months or more? Thanks in advance Ken Green -- Kendall B. Green Duke University Medical Center Durham, NC 27710 kgreen@dukeac.ac.duke.edu or ...mcnc!escgate!dukeac!kgreen
karl@ddsw1.MCS.COM (Karl Denninger) (07/03/89)
>Item 4105 (0 responses) by kgreen at dukeac.UUCP on Sun 02 Jul 89 09:35 >[Kendall B Green] Subject: Seagate 251 and RLL controllers > >I have a Seagate 251 Hard Drive that I want to put into a 80386SX >machine. I would like to use an RLL controller to increase the >capacity and decrease the access time. From discussions here If it's a recent model it should work ok (green light .vs. red light). The red light models don't work well at all.... don't do it with those. We use them here RLL all the time, and have yet to have a failure that wasn't related to the heads crashing (grrrr); that can't be caused by the recording method! -- Karl Denninger (karl@ddsw1.MCS.COM, <well-connected>!ddsw1!karl) Public Access Data Line: [+1 312 566-8911], Voice: [+1 312 566-8910] Macro Computer Solutions, Inc. "Quality Solutions at a Fair Price"
root@swituc.UUCP (Admin) (07/07/89)
We use RLL controllers and ST251s (60 MB useable) in all of our AT clones and have had absolutely no problems to date. These machines have been in use for nearly a year in this configuration. My machine also has a ST238R (RLL 30 MD) on the same controller and there are no problems mixing the MFM and RLL disks. I hope this answers your query. Pat Berry Director of R&D Sonoran Western Ind, Inc. uunet!arizona!swituc!pmb
nghiem@walt.cc.utexas.edu (Alex Nghiem) (07/09/89)
In article <145@swituc.UUCP> root@swituc.UUCP (Admin) writes:
!>We use RLL controllers and ST251s (60 MB useable) in all of our AT
!>clones and have had absolutely no problems to date. These machines have
!>been in use for nearly a year in this configuration.
My Seagate manual says your warranty is void if you use any Seagate
drive without an "R" on the end with an RLL controller. You should
use the ST251R instead of the ST251.
keithe@tekgvs.LABS.TEK.COM (Keith Ericson) (07/09/89)
In article <14998@ut-emx.UUCP> nghiem@walt.cc.utexas.edu (Alex Nghiem) writes: >In article <145@swituc.UUCP> root@swituc.UUCP (Admin) writes: >!>We use RLL controllers and ST251s (60 MB useable) in all of our AT >!>clones and have had absolutely no problems to date. These machines >!>have been in use for nearly a year in this configuration. > >My Seagate manual says your warranty is void if you use any Seagate >drive without an "R" on the end with an RLL controller. You should >use the ST251R instead of the ST251. > And people wonder why Seagate is considered to be a "second rate" drive supplier! It's because of these scare tactics, making the uninformed computer initiate think that there is some magic to RLL that will fry electronics, damage heads and warp platters if it's "done to" a non-RLL-certified drive. Ptooey! There is no way Seagate could even KNOW if you had "RLL'ed" your drive, anyway. To threaten voiding the warranty (is it a "lifetime" warranty that's good for the life of the drive - when the drive quits working it's life and the warranty are over? :-) is simply a tactic used to "convice" you that you need to pay the extra bucks for their RLL drive. kEITHe
tcm@srhqla.SR.COM (Tim Meighan) (07/11/89)
In article <5536@tekgvs.LABS.TEK.COM> keithe@tekgvs.LABS.TEK.COM (Keith Ericson) writes: >In article <14998@ut-emx.UUCP> nghiem@walt.cc.utexas.edu >(Alex Nghiem) writes: > >>My Seagate manual says your warranty is void if you use any Seagate >>drive without an "R" on the end with an RLL controller. You should >>use the ST251R instead of the ST251. > >And people wonder why Seagate is considered to be a "second rate" >drive supplier! It's because of these scare tactics, making the >uninformed computer initiate think that there is some magic to RLL >that will fry electronics, damage heads and warp platters if it's >"done to" a non-RLL-certified drive. Ptooey! Well, let's be fair about this. I really don't think that Seagate is trying to "scare" us into thinking we'll ruin a 251 drive mech by hooking it up to an RLL controller. What they are saying is that they won't honor the warranty on a drive mech USED AS AN RLL DRIVE that hasn't been certified to have a platter surface capable of handling RLL encoding, which is, after all, higher density than MFM encoding. Note that failure of a drive mech isn't always mechanical failure; it could be that the drive just doesn't read and write data reliably. So, by telling you not to use anything but a certified drive mech for RLL encoding, Seagate is just trying to protect itself from legal hassles. You may or may not agree with their policy of certifying specific drive mechs as suitable for RLL encoding, and charging more for such drive mechs. I think such a policy is reasonable, but it is certainly a matter of personal opinion. In any event, regardless of what you think of Seagate and the quality of their products, this by itself hardly qualifies them as a second-rate company. BTW, it is extremely easy for a manufacturer to determine if a drive mech has been formatted for RLL encoding, so Mr. Ericson's assertion that there is no way they would know if you did such a thing is untrue. What were you going to do, Keith, a low-level MFM re-format of your BROKEN drive so they couldn't tell it had once been RLL? Good luck! :-) Tim Meighan Silent Radio "I've got one, two, three, four, five . . . . drive heads working overtime!"
karl@ddsw1.MCS.COM (Karl Denninger) (07/13/89)
>Item 4249 (0 responses) by tcm at srhqla.SR.COM on Wed 12 Jul 89 04:26 >[Tim Meighan] Subject: Re: Seagate 251 and RLL controllers >BTW, it is extremely easy for a manufacturer to determine if a drive >mech has been formatted for RLL encoding, so Mr. Ericson's assertion >that there is no way they would know if you did such a thing is untrue. This is providing that Seagate actually takes the media out and checks it. If the drive still works MFM, you simply reformat it MFM; Seagate then cannot tell what you did prior to that time (of course you ALSO can't exchange it then! :-) If it does not work at all, then it would be more hassle than it's worth for Seagate to get the drive working well enough to see what the encoding format on the platters is. In any event, I've been told that they don't check them beyond a very simple functional test - - they just scrap the things and send you another unit (this from net reports and someone who used to work in their tech department). -- Karl Denninger (karl@ddsw1.MCS.COM, <well-connected>!ddsw1!karl) Public Access Data Line: [+1 312 566-8911], Voice: [+1 312 566-8910] Macro Computer Solutions, Inc. "Quality Solutions at a Fair Price"
keithe@tekgvs.LABS.TEK.COM (Keith Ericson) (07/13/89)
In article <723@srhqla.SR.COM> tcm@srhqla.SR.COM (Tim Meighan) writes: >Well, let's be fair about this. I really don't think that Seagate is >trying to "scare" us into thinking we'll ruin a 251 drive mech by hooking it >up to an RLL controller. What they are saying is that they won't honor >the warranty on a drive mech USED AS AN RLL DRIVE that hasn't been certified >to have a platter surface capable of handling RLL encoding, which is, after ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ >all, higher density than MFM encoding. ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ No, no, no, no, no! The flux changes per inch is NOT higher in RLL than it is in MFM. One of the consequences of RLL encoding is that the timing constraints on exactly WHEN those flux changes occur is much tighter, and a "crummy" surface won't be able to maintain those timing specs. But the actual fcpi is the SAME. Yes, each byte of recorded information represents, on average, 1.5 bytes of "real" information, but what the platters sees is no different between MFM and RLL. >Note that failure of a drive mech isn't always mechanical failure; it could >be that the drive just doesn't read and write data reliably. If RLL use of a drive causes mechanical damage there's really something wrong goning on... > So, by telling >you not to use anything but a certified drive mech for RLL encoding, Seagate >is just trying to protect itself from legal hassles. No, what it is telling you is "We made this big batch of drives; we tested them all to see which ones will work RELIABLY with RLL. Those we charge more money for." (Guess where 5% and 10% carbon resistors came from - the same batch, but the 5% were tested and made the spec; the 10% parts didn't.) >You may or may not agree with their policy of certifying specific drive >mechs as suitable for RLL encoding, and charging more for such drive mechs. >I think such a policy is reasonable, but it is certainly a matter of >personal opinion. In any event, regardless of what you think of Seagate >and the quality of their products, this by itself hardly qualifies them >as a second-rate company. >BTW, it is extremely easy for a manufacturer to determine if a drive >mech has been formatted for RLL encoding, OH? How? > so Mr. Ericson's assertion >that there is no way they would know if you did such a thing is untrue. >What were you going to do, Keith, a low-level MFM re-format of your >BROKEN drive so they couldn't tell it had once been RLL? Look, if an non-RLL-certified drive fails to work reliably with an RLL controller, it will be by loss of bits - failure to read, write, and/or verify data. It's not going to go up in smoke, fry IC's, warp platters or sieze bearings! So, Yes - I'd re-format it with an MFM controller and use it as such. I've done it many times (more than I had hoped I'd have to) with Miniscribe 3053's. > Good luck! :-) Look, I KNOW I'm pushing the spec to connect an RLL controller to a drive not necessarily certified for it. But I don't see Maxtor nor Micropolis telling me, in effect, that I risk damaging the whole drive by doing it. I mean, get REAL, Seagate!!! I'm also pushing the spec to format 1200 cylinders on a Maxtor drive certified to have 1024. But I've learned that these manufacturers make quality products, I take my chances, and get a little extra. I haven't had that experience with Seagate. kEITHe
bobmon@iuvax.cs.indiana.edu (RAMontante) (07/13/89)
-No, what it is telling you is "We made this big batch of drives; we tested -them all to see which ones will work RELIABLY with RLL. Those we charge -more money for." Or, "Some of the drives failed the Quality Assurance tests with RLL formatting, but are okay for MFM. Those we charge less money for." :-) (Okay, I know things didn't start out that way.) ->BTW, it is extremely easy for a manufacturer to determine if a drive ->mech has been formatted for RLL encoding, - -OH? How? Speculation... MFM controllers seem to put 17 sectors per track. The RLL controllers I've seen appear to put 25 sectors (plus or minus a couple) on a track. So I could determine MFM vs. non-MFM by looking for sector-marking information. It's a heuristic, but hey...