--- On Fri, 6/14/13, Geoffrey Oltmans <[email protected]> wrote: All the third party utilities I have used on the drive "kinda work". The one I'm using now, Lido will let me use the drive, but writing anything to disk is S--L--O--W.
----- If it was used on a Mac Plus or SE, it probably was formatted with an interleave other than 1:1. The old drives with no onboard cache RAM, though slow, were too fast for the SCSI in the first models of Macintosh. IIRC the Plus required a 3:1 interleave and the SE a 2:1. The idea is for most reads or writes the next block read or written will come around just in time. Using such a drive on a newer Mac will be slower because the computer has to spend more time waiting. Thus the best thing to do will be to copy everything off the drive, reformat it to 1:1 interleave, then copy the data back. Only some very old utilities allow you to select the interleave, I dunno if a newer formatter will change it to 1:1. Might have to dig up one of those old programs or find a PC with a good SCSI controller like an Adaptec 2940 to low level format it.* Hard drives with cache RAM should always be formatted with a 1:1 interleave because the drive will store writes in RAM then put them on disk as soon as it can. At some point (after the first drives with cache) read ahead was added so that the drive would start filling up the cache with data from the file being currently read, so it'd be ready faster when requested. *I used that to clear up issues no Mac drive utility could fix. Low level format with a 2940 on a PC. Next step is to use FDISK to make a single partition. If the drive is going to be HFS+, enable FAT32 support. Then high level format with FAT16 or FAT32. Finally, connect the drive to a Mac, boot up and erase the drive to HFS or HFS+. No hacked utility or Apple drive firmware required! The low level formatting structures of HFS/FAT16 and HFS+/FAT32 are either identical or close enough that Mac OS can simply overwrite the high level format. -- -- ----- You received this message because you are a member of the Vintage Macs group. The list FAQ is at http://lowendmac.com/lists/vintagemacs.shtml and our netiquette guide is at http://www.lowendmac.com/lists/netiquette.shtml To post to this group, send email to [email protected] To leave this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/vintage-macs Support for older Macs: http://lowendmac.com/services/ --- You received this message because you are subscribed to the Google Groups "Vintage Macs" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/groups/opt_out.
