Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!cs.utexas.edu!samsung!brutus.cs.uiuc.edu!wuarchive!mit-eddie!mit-amt!snorkelwacker!spdcc!merk!xylogics!cloud9!jjmhome!m2c!wpi!ear From: ear@wpi.wpi.edu (Eric A Rasmussen) Newsgroups: comp.sys.ibm.pc Subject: Re: MFM as an RLL drive? Message-ID: <6252@wpi.wpi.edu> Date: 13 Dec 89 02:38:08 GMT References: Reply-To: ear@wpi.wpi.edu (Eric A Rasmussen) Distribution: comp Organization: Worcester Polytechnic Institute, Worcester ,MA Lines: 32 In article mlm@cs.brown.edu writes: > > Is it possible to use a MFM hard disk drive with an RLL > controller? Are there particular MFM drives that will do it? > How would I tell? While the answer to your first question is technically yes, I cannot emphasize enough how bad an idea it is. Unless a drive is specifically designed for RLL, which means that it has a higher quality media inside it, you SHOULD NOT try to format it as an RLL drive. This is equivalent to formatting a double density disk, designed to hold 360k of data, as a 1.2 Meg disk, or a 720k disk as a 1.44 Meg disk. While this will not physically hurt the drive or the disk, the integrity of the data you store on the disk will be very questionable. What will typically happen is that everything will appear to work, the drive will format successfully, and you will copy your files onto it, and boy will you feel clever. Then, maybe immedietly, maybe after a few weeks, you will start to get errors. Data will be lost forever or corrupted, programs will stop working, and soon the entire disk will become unusable. The basic problem is that the coating on the disk is not designed to handle the density of data used by the RLL format, and it WILL 'forget' what you have stored there. There. I hope I have convinced you that it is a bad idea. As to how to tell if a drive is designed for RLL or not, you would either have to look in a manual for your drive, or consult with your dealer, or a dealer of those brand drives. _ _ +-=-=-=-=-=-=-=-=-+ |_ ,_ . _ |_} _ _ ,_ _ _ _ _ ,_ | ear@wpi.wpi.edu | |_ | | |_ | \ |_\ _> | | | |_| _> _> |_' | | | ear%wpi@wpi.edu | --< A real engineer never reads the instructions first! >-- +-=-=-=-=-=-=-=-=-+