jchin@wimsey.bc.ca (Joseph Chin) (05/09/91)
A while ago, I posted about my SCSI problems where my NeXT with a Micropolis 1588-15 hard drive would perform flawlessly when the Micropolis is the only SCSI device in the system. But as soon as other SCSI devices (such as the HSD Scan-X and PLI SuperFloppy 2.8) are attached to the chain, the system would puke out "sd0: Incomplete disk transfer ..." error messages. At worst, the system couldn't boot up when the PLI SuperFloppy 2.8 was attached. After months of testings (tried out various very creative terminating alternatives) and lots of help from NeXT, Micropolis, and HSD, the problem has been solved!! Micropolis has been very helpful and patient throughout this whole ordeal. Adi Antariksa (Micropolis tech support) sent me firmware upgrades after firmware upgrades, and finally, their latest and best HSP4 firmware (also used in their new 4ms SCSI drives) fixed the problem and everything couldn't be better! The Micropolis 1588-15 is very fast and reliable. Using the read tests in "disk" (1000 reads in 16 sector increments, standard test used by authors of The Formatter to compare performance), the transfer rate consistently average over 1.1MB/second! A 330MB Maxtor drive (in an 040 cube) gets less than 600KB/second in the same test. Other drives I have tested (Wren and Fujitsu 226x) get around 700-800KB/second. BTW, although the SCSI connector in the NeXT (040 slabs and cubes) is SCSI-2, the actual SCSI interface is only SCSI-1. This is what I've been told by a NeXT employee. The SCSI-2 connector was used because it takes up less room on the backpane of the system board, thus, leaving enough room for the 10Base-T Ethernet jack. Maybe someone can verify this. Thanks to all those who helped me in solving this SCSI problem. :-) Joe jchin@van-bc.wimsey.bc.ca -- ************************************************************** * "Kill the body and the head will die" (Hunter S. Thompson) * * NeXT --> The ultimate electronic publishing platform! * ********** Joseph Chin --> jchin@van-bc.wimsey.bc.ca *********