🚀 go-pugleaf

OK - wegen der Nachfrage hier die Infos  aus  dem  DALLAS  SEMICONDUCTOR
"1990-1991 product data book":

"The  DS2223  and  DS2224  EconoRAMs  are  fully  static,  micropowered,
read/write memories packaged in a low-cost TO-92 package. The DS2223  is
organized as a serial 256*1 bit static read/write memory.  The  DS2224's
first 32 bits are lasered in  with  a  unique  ID  code  at  the time of
manufacture;  the  remaining  224 bits  are  static  read/write  memory.
Signalling  for  reading  or  writing  is  reduced to just one interface
lead." (p. 306)
"The open-drain driver allows the EconoRAM to  be  powered  by  a  small
standby energy source, such as a single  1.5  volt alkaline battery, and
still have the ability to produce TTL/CMOS output levels." (p. 308)
"operating current: 36 nanocoulombs per 264 time  slots  @1.5V,  Standby
current typical 0.2nA, max. 15nA" (p. 311)


"The DS2400 Silicon Serial Number is a device which  contains  an  8-bit
model  number,  a  unique  48-bit  serial  number,  and  an 8-bit cyclic
redundancy check value embedded in  silicon.  Signalling  necessary  for
reading or writing is reduced  to  just one interface lead. The familiar
TO-92 package  provides  a  small, low-cost enclosure. Power for reading
and  writing  is derived from the data line itself with no need  for  an
external power source." (p. 838)

"The DS1204U Electronic Key is a miniature security system  that  stores
64 bit of user-definable identification code and a 64-bit security match
code that protects 128 bits of read/write nonvolatile memory. The 64-bit
identification code and the security match code are programmed into  the
key via a special program mode operation.  After  programming,  the  key
follows a procedure with  a  serial  format  to retrieve or update data.
Interface  cost  to  a  microprocessor is minimized by on-chip circuitry
that  permits data transfer with only three signals: Clock (CLK), RESET\
(RST\), and Data Input/Output (DQ). Low pin count and a guided entry for
mating receptable overcome mechanical problems normally encountered with
conventional integrated circuit  packaging,  making  the  device  trans-
portable and user-insertable." (p. 555)
This device is also available in a coin-shaped metal package (DS1990, p.
835).

Es gibt da noch so ein paar  tolle  Sachen:  z.B.  den  'TimeKey':  "The
TimeKey  is  set  to  expire  from one day to 512 days or  infinity,  as
specified by the customer. The  TimeKey  starts  its  countdown from the
first access by  the  end  user". Wenn man Software schuetzen will, gibt
das  einige  tolle Moeglichkeiten - man sollte das halt  nur  nicht  als
Dongle an einen  Port  haengen,  der  dann  wieder  mit  irgendwas nicht
zusammenarbeitet ...


International distributors - west germany:
Atlantik Elektronik GmbH
49-89-857-000
Astek Elektronik Vertriebs GmbH
49-4191-8007-0


Bei Atlantik Elektronik muesste man das  Datenbuch  oder  zumindest  die
Datenblaetter fuer einzelne  ICs  kriegen koennen. Ich weiss aber nicht,
was die kosten.  Das  Datenbuch enthaelt aber auch andere tolle Sachen -
nicht nur aus dem Bereich Seriennummern und Sicherheit.
-------------------------------------------------------------------------------
Michael Schwingen, Ahornstrasse 36, W-5100 Aachen, Germany
michaels@messua.informatik.rwth-aachen.de
PLEASE KEEP MAIL FROM OUTSIDE GERMANY SHORT-I HAVE TO PAY FOR INCOMING MAIL