Hmm, interesting. K.scsi is not mentioned in my HSC50/70 docs. Does anyone have any docs contains K.scsi tech info?
Thanks again, Tim -----Original Message----- From: Simh [mailto:simh-boun...@trailing-edge.com] On Behalf Of Johnny Billquist Sent: Monday, March 6, 2017 6:47 PM To: simh@trailing-edge.com Subject: Re: [Simh] CI750 tech docs and VAX firmware On 2017-03-06 15:03, Timothe Litt wrote: > There were also HSC40 & hsc60. Right. Pretty similar to all the others. The differences (as far as I can remember) were mostly on the number of SDI/STI ports available, and the amount of cache in the machine. > The differences in the hsc family members were the processor, cache, > load device, number of channels, and maximum number of ports. Some > models were field-upgradable. Also, later models supported > (reluctantly) the K.scsi module, which allowed the HSC to serve SCSI > disks and tapes. (SCSI was carefully analyzed & found to have > reliability/data integrity issues; DEC's answer was DSSI. Rather like > Beta & VHS - "good enough, but cheaper" won.) Right. However, to use the K.scsi, you actually needed to upgrade. The HSC90 with the capability to use K.scsi was the HSC95. I don't think the HSC70 could at all. The 40 and 60 could, I think, but I wonder if they then were renamed 45 and 65. I think I still have some documentation somewhere, but it would take some digging to find this. > At some point, support for 18-bit disks (576 byte sectors) was dropped. > The HSC50 definitely had it; the HSC90 did not. I'm unsure about the HSC70. Unless I remember totally wrong, only the HSC50 could do 576 byte sectors. It was dropped in a pretty early version of CRONIC, before support for any other HSC controller existed. Johnny _______________________________________________ Simh mailing list Simh@trailing-edge.com http://mailman.trailing-edge.com/mailman/listinfo/simh
