mmm@reaper.Chi.IL.US (Michael Marvin Morrison) (05/27/91)
Does anyone happen to have the pinout laying around to the old 8" Shugart floppies? It appears to be a ~50 pin connector (gee, what are all those extra lines for :-) Any help would be appreciated. -- Michael M Morrison /| |\ mmm@reaper.chi.il.us <or> | | Cold Steel on Ice | | reaper!mmm@miroc.chi.il.us \| |/
ben@epmooch.UUCP (Rev. Ben A. Mesander) (05/29/91)
In article <mmm.1539@reaper.Chi.IL.US> mmm@reaper.Chi.IL.US (Michael Marvin Morrison) writes: >Does anyone happen to have the pinout laying around to the old 8" Shugart >floppies? It appears to be a ~50 pin connector (gee, what are all those >extra lines for :-) Any help would be appreciated. It's not terribly standardized (one of the reasons 8" floppies lost in popularity). It's also not terribly useful on an Amiga; the data clock rate is different for 8" and the 5.25/3.5" drives. -- | ben@epmooch.UUCP (Ben Mesander) | "Cash is more important than | | ben%servalan.UUCP@uokmax.ecn.uoknor.edu | your mother." - Al Shugart, | | !chinet!uokmax!servalan!epmooch!ben | CEO, Seagate Technologies |
kenw@skyler.arc.ab.ca (Ken Wallewein) (06/03/91)
The pinout seems to be pretty standard, but implementation/usage did vary
a bit. e.g. sometimes the drive select lines were "multiplexed". Anyway,
here's how it's defined in the docs for my S100 controller and CDC drives:
(all lines active low; "->" means controller-sent, "<-" means drive-sent)
-- All odd-numbered lines, e.g. 1,3,5...49, all on one side of the
connector, are grounded. This is to improve signal propagation on
the ribbon cable.
-> 2: LOW-CURRENT, track number is > 43; reduce head write current for DSDD
-> 6: " (may be same as above or unused - not clear on this)
8: not used
<- 10: 2SIDED, disk is double-sided
<- 12: DISKCHG, door was opened (may not be provided)
-> 14: SIDESEL, side/head select
-> 16: INUSE, turns on "in use" LED, may latch door
-> 18: HLD, head load (8" drive load the heads instead of starting the
motor, which never stops).
<- 20: IP, index pulse
<- 22: RDY, drive is ready
<- 24: SECTOR, sector hole detected (for hard-sectored disks only)
-> 26: DRVSEL1, drive select 1
-> 28: DRVSEL2, drive select 2
-> 30: DRVSEL3, drive select 3
-> 32: DRVSEL4, drive select 4
-> 34: DIR, head step direction
-> 36: STEP, step the heads
-> 38: WDATA, write data
-> 40: WGATE, write enable
<- 42: TRK00, drive is at track 0 (home)
<- 44: WPROT, disk is write protected
<- 46: RDATA, raw read data
<- 48: separated data, not usually used
<- 50: separated clock, " " "
As I understand it, 8" floppies run at 500Khz, as opposed to 250 Khz for
5 1/4" drives. Not sure about 3 1/2", but seem to recall they're like 8"
drives. Of course, then one has to allow for density.
I've often thought I wouldn't mind hooking up my DSDD CDC 8" drives to
my Amy. They were fast, reliable, held a lot of data, and I have more
blank disks sitting around than I know what do do with.
--
/kenw
Ken Wallewein A L B E R T A
kenw@noah.arc.ab.ca R E S E A R C H
(403)297-2660 C O U N C I Ldoctorj@en.ecn.purdue.edu (Jeffrey W Davis) (06/04/91)
In article <KENW.91Jun2194637@skyler.arc.ab.ca> kenw@skyler.arc.ab.ca (Ken Wallewein) writes: > > As I understand it, 8" floppies run at 500Khz, as opposed to 250 Khz for >5 1/4" drives. Not sure about 3 1/2", but seem to recall they're like 8" >drives. Of course, then one has to allow for density. > > I've often thought I wouldn't mind hooking up my DSDD CDC 8" drives to >my Amy. They were fast, reliable, held a lot of data, and I have more >blank disks sitting around than I know what do do with. I have also thought of interfacing to an 8" floppy drive. Actually it is a high capacity 5 1/4" drive with an 8" drive interface. I gave up on the idea due to the double frequency requirement. By the way, 3 1/2" drives run at the same frequency as 5 1/4" drives. Does anyone know an easy way to adapt an 8" drive to the Amiga without having to make a Zorro card containing an 8" drive interface? Like an adapter that does some kind of trick to keep both the computer and the drive happy... tackling the frequency difference problem? There are high capacity 8" (type-interface) drives available that will hold in excess of 3 Meg. on a 5 1/4" floppy; at an impressive speed! I have one that used to be connected to my Radio Shack CoCo through a WD floppy controller. Now if it can connect to a CoCo, surely there is a simple way to connect it to the Amiga. > >Ken Wallewein A L B E R T A >kenw@noah.arc.ab.ca R E S E A R C H *********************************************************** * Jeff Davis * Relax! And get into /// * * doctorj@en.ecn.purdue.edu * the STRESS!!! /// * * * \\\///030 * * * -Gigahertz!- Amiga\XX/ 882 * *********************************************************** -=[ In Stereo Where Available ]=-