Archived posting to the Leica Users Group, 2001/04/04
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]> Only if you are scanning and accessing the Iomega at the same time. Even that doesn't matter... > Each peripheral on the SCSI II (or SCSI-3) bus negotiates a transfer rate > with the host. Fast and slow devices run at their negotiated speeds. The > whole bus does not slow down to the speed of the lowest peripheral. Correct, and only the data phase is at the device speed, and as you say, that is negotiated with EACH transfer...which is why what you said on top isn't true. > Things get different on a LVD (low voltage differential) bus when > attaching > SE (single ended) peripherals. If memory serves the maximum > transfer on a SE > bus is 20 megatransfers a second (20 MB if it's 8 bits wide, 40 > MB if its 16 > bits wide) Typically, SE and differential operate at the same speed, that only governs signal integrity...as in cable length and number of drives on the cable. The LVD drives can run in either SE or DE on a SCSI-160 bus with no problem. > One question would be just how fast can a scanner generate data? Exactly. That is why even SCSI II is far faster than most any scanner can generate data...so even asynch SCSI works fine for most scanners...and going to SCSI II or Ultra etc. won't make your scans any faster...