New subject: mini connectors that look like centronics but are much smaller....where?

17 May 2001

"Hans Franke" &lt;Hans.Franke(a)mch20.sbs.de&gt; said:
...
  Well, as long as you think along a 'real' drum
with flying heads
 etc. you're right, but there is a simple solution - take a card
 board tube and warp regular cassete tape around, and let a head
 read/write this tape ... if you take an old style washing powder
 drum (ca. 30 cm diameter / 1 ft) you get a lenght of about 1m
 (3 ft 4") - what was the usual speed of cassetes ? 4 cm/s ? I'm
 not shure (Tony ?), as a rough estimation you get a track size
 of some 3 kByte and an average access time of 12s not to bad ... 
  I have this really sick and perverted habit of picking up 
unusual items just in case they might be useful for future
projects. All of this talk about building a drum storage 
reminded me of something that I added to my eclectic resource
pile a few years ago, an old drum type fax machine.

  But, when it comes to adding mass storage to a digital 
computer system, IMHO I can't think of anything faster, 
easier, or more reliable than the old Commodore 1541.
 * The DOS is built-in.
 * Only the system side communication routines need to be
   written and there is commented source code to use as
   examples.
 * The drive side communication routines can also be 
   rewritten.
 * Since the communication with the drive is normally
   handled with very robust handshaking, the speed of the 
   computer system is totally unimportant. This also means
   that disk I/O can be easily interrupted.
 * And additional drives can be daisy-chained on the same 
   bus. 
 Regards,
 --Doug
=========================================
Doug Coward                
@ home in Poulsbo, WA

Analog Computer Online Museum and History Center
http://www.best.com/~dcoward/analog
=========================================

Magnetic Drum Storage WAS Re: Using audio cassette