ABN.ISCAMS@usc-isid@sri-unix.UUCP (09/27/83)
Yes, the Morrow DJ/DMA Floppy Disk Controller will drive 5" as well as 8" disks. I quote from their Tech Manual (Rev 1, Apr 82, Morrow Designs, all rights reserved), "The Disk Jockey/Direct Memory Access (DJDMA) Floppy Disk Controller is a single board S-100 subsystem. It communicates with both 8 inch and 5 1/4 inch floppy disk drives. Up to eight drives may be connected to the controller - with the limitation that no more than four of each type can be accomodated. "Special programmable bipolar LSI logic makes it possible to read and write media with almost any format, be it hard or soft sectored. Presently the controller supports soft-sectored IBM compatible 8 inch media and hard- sectored North Star compatible 5 1/4 inch media. In the spring of 1982, IBM and Radio Shack 5 1/4 inch soft-sectored media will also be supported. Existing controllers in the field can be upgraded by replacing two of the ICs on the unit. ... And in the source code for my CBIOS (provided by Morrow for my own 8"/ 5Meg HD system), I see drivers for Fujitsu M2301B, M2302B, Shugart SA4000, and Memorex winchesters, Seagate ST-506, ST-412 and CMI CM-5619 8" drives, and the North Star CP/M 1.4 and 2.X SSSD 35 tracks, SSDD 35 track, DSDD 35 track, plus same for 2 and 4 k groups. My vendor down in Alabama talks about interfacing Tandon DSDD 5 1/4 drives with no real problem. So, I guess so. Hope this helped. David Kirschbaum SGM, USA HQ XVIII Abn Corps
MMOON.ES@PARC-MAXC.ARPA@sri-unix.UUCP (09/27/83)
5" & 8" disks are generally incompatible on the same controller *unless* you have some convienient (read that software controllable) means of changing the 179X disk controller chip's clock frequency. The last time I looked, 5" drives were transfering data at 1/2 the rate of 8" drives, no matter whether one is using single or double density, but I was looking at 48 tpi, 40 track per side drives; get the some info on the 96 tpi, 80 track per side drives to be certain. There are several Morrow double densitity controllers; I have one of the discontinued I/O mapped boards which is incapable of DMA, & this device *definitely* will not support connectors to 5" drives or clock rate changes, at least not without extensive hatchet work. Good luck if you decide to continue. I would appreciate being kept posted in that event. Moon
marti@rand-unix@sri-unix.UUCP (09/28/83)
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