dve@zooid.UUCP (David Mason) (09/25/90)
Hello all. I asked this question a while ago on another system, but didn't get a decent answer at the time. So, here goes. I have a 70 mb 28ms full height Micropolis 1330 (I think, or 1335) hard disk. It currently has an MFM controller. I was told by a couple of individuals that it would be safe to RLL this drive (to about 110mb, I think), and a couple of other people told me this drive could NOT be safely RLL'd. I'd like to know the "real" answer. I called what support Micropolis had here in Canada (not much) and only recieved a very vague answer. So can someone give me an authoritative answer? The drive has no errors on it at all (I've checked it with a couple of programs) and is about 2 years old (possibly older, I bought it used). The drive is constantly full, and I could really use the extra 30 megs. Thanks.
mlord@bwdls58.bnr.ca (Mark Lord) (09/26/90)
In article <2a81P1w162w@zooid.UUCP> dve@zooid.UUCP (David Mason) writes: > >I have a 70 mb 28ms full height Micropolis 1330 (I think, or 1335) hard >disk. It currently has an MFM controller. I was told by a couple of >individuals that it would be safe to RLL this drive (to about 110mb, I >think), and a couple of other people told me this drive could NOT be safely >RLL'd. I'd like to know the "real" answer... Back it up, borrow an RLL controller from a close friend, and try it. If it formats with only a few bad sectors, then buy an RLL controller and count your megabytes. Otherwise, reformat it with MFM. Drives from 2 years ago stand an excellent chance of working with RLL, since back then nobody was sampling drives specifically for MFM/RLL. That is probably why older drives tended to have fewer bad sectors on average (MFM), as well. My old Miniscribe works fine, with zero bad sectors under MFM, RLL, and ADRT/ARLL. My new Seagate 251-1 worked only under MFM reliably. Your mileage may vary, so try before you buy. -- ___Mark S. Lord__________________________________________ | ..uunet!bnrgate!mlord%bmerh724 | Climb Free Or Die (NH) | | MLORD@BNR.CA Ottawa, Ontario | Personal views only. | |________________________________|________________________|
pdwalker@bcarh471.bnr.ca (Paul D Walker) (09/26/90)
In article <2a81P1w162w@zooid.UUCP> dve@zooid.UUCP (David Mason) writes: >Hello all. I asked this question a while ago on another system, but didn't >get a decent answer at the time. So, here goes. > >I have a 70 mb 28ms full height Micropolis 1330 (I think, or 1335) hard >disk. It currently has an MFM controller. I was told by a couple of >individuals that it would be safe to RLL this drive (to about 110mb, I >think), and a couple of other people told me this drive could NOT be safely >RLL'd. I'd like to know the "real" answer. I called what support Micropolis >had here in Canada (not much) and only recieved a very vague answer. So can >someone give me an authoritative answer? The drive has no errors on it at >all (I've checked it with a couple of programs) and is about 2 years old >(possibly older, I bought it used). The drive is constantly full, and I >could really use the extra 30 megs. > >Thanks. I asked the same question about 8 months ago when there was a large rage on about MFM vs RLL and what could be done and not done. After listening to the arguments, I decided to go out and buy a RLL controller for my AT. In the 8 months since I have had the card, I have sucessfully formatted and used 2 Seagate 251 type 40 hard drives as 65 meg drives. I have also sucessfully used a 110 meg Priam (type 9) hard drive as a 170 meg drive for 3 months with absolutely no problem. Other than the increase in disk space that I got from this, I have increased my DTR (data transfer rate) from 250k/sec to 715k/sec. Now, I am sure that we are going to hear from some people about how it is EVIL to have done this, and that my warrenty has been voided (I have none) and that my drives are going to melt down and be destroyed at any time. Hogwash. I will say that on an older drive, using a RLL controller MAY cause you some problems. However, I am of the opinion that the drives made today are of a good enough quality (with both timing and precision) that they can easily handle the increased timing demands of an RLL controller. Notice that both types of drives that I have used are of a known 'good quality' My controller is a DTC 7287 If you have a good hard drive, (access time <= 40ms) then go out and get the card. I doubt that you will have a problem. Dont forget to change the interleave (usually 1:1) to get the enhanced throughput. PS: by the way. If you are crammed up at 70meg of disk space, then the extra 30 meg you will fill up in a short order. :) /**************************************************************************** * Paul D. Walker PHONE : (613)765-2590 * * Bell-Northern Research, Ltd. BITNET: pdwalker@bnr.car * * Ottawa Ontario Canada USENET: ...!uunet!bnrgate!bcarh471!pdwalker * ****************************************************************************/
dve@zooid.UUCP (David Mason) (09/26/90)
mlord@bwdls58.bnr.ca (Mark Lord) writes: > Back it up, borrow an RLL controller from a close friend, and try it. > > If it formats with only a few bad sectors, then buy an RLL controller > and count your megabytes. Otherwise, reformat it with MFM. From what I've been told, the main hazard of formatting an MFM drive RLL comes from long term usage - the drive would be more likely to expire since RLL uses "more" of the disk. So a short term test wouldn't help. However, I believe if I periodically reformat the hard disk (low level, with a program such as Optune) I should be ok. Thanks for your comments. They are useful to me.
dve@zooid.UUCP (David Mason) (09/26/90)
pdwalker@bcarh471.bnr.ca (Paul D Walker) writes: > PS: by the way. If you are crammed up at 70meg of disk space, then the > extra 30 meg you will fill up in a short order. :) Thanks for the comments. Yes, I'm well aware that the more disk space I have,the more data that will mysteriously appear. However, I just want room for my major applications, I don't mind swapping data so much. But we do have a point of disagrement. A previous message stated that drives older than two years were better for RLLing (if they were certified for MFM, but not tested for RLL). You claim that newer drives are better. I don't think this one can be resolved though, because you both have points.
ssingh@watserv1.waterloo.edu ($anjay [+] $ingh - Indy Studz) (10/05/90)
In article <4431@bwdls58.UUCP> mlord@bwdls58.bnr.ca (Mark Lord) writes: > >sectors under MFM, RLL, and ADRT/ARLL. My new Seagate 251-1 worked only ^^^^^^^^^^^ What is that??? -- "No one had the guts... until now..." -New Anti-Repression Convert (NARC) |-NARCotic $anjay [+] $ingh ssingh@watserv1.[u]waterloo.{edu|cdn}/[ca] -| watserv1%rn alt.CENSORED: UW Provost sez "THINK SAFE THOUGHTS; AVOID NASTY ALT FEEDS; & PROTECT YOURSELF: WEAR A CONDOM ON YOUR HEAD. Call x-2809. Let's Talk.