Hans,
You missed the important part of using a newspaper press as a papertape
reader...It is MUCH wider than a single byte.
No revising the calculations to use the actual roll sizee of a commercial
press, and using 10 bytes / sq in [arrogant american here] we start to see
some interesting numbers for capacity and speed....
Not neaarly as fast as other storage media still...but you get the advantage
that it is readable by a human [yes I have punched and read PDP-8 BIN loader
tapes by hand!]. Very fault tolerant [wish I could find a pack of the old
adhexive paper table patches]. Actually no technology is needed to read it.
If we are going to use more advanced technology but still keep the basis
premise, then "reasonable" stamped indentations or even holes could be made
into a very durable media. We sould want to keep the density at or near "eye
readable" levels to eliminate the need for equipment to interpret the
information.
When every one stops laughing (or groaning) compare this concept to the
ancient recordings we have [hieroglyphics, cuniform, etc] and you will see
it is not so different and they have lasted (Basically) intact in many cases
for thousands of years. Even the ones that are severely damaged, still
provide readable content.
>>> -----Original Message-----
>>> From: cctalk-bounces_at_classiccmp.org
>>> [mailto:cctalk-bounces_at_classiccmp.org] On Behalf Of Hans Franke
>>> Sent: Friday, August 13, 2004 3:27 PM
>>> To: General Discussion: On-Topic and Off-Topic Posts
>>> Subject: Paper Tape (was: Let's develop an open-source
>>> media archive standard )
>>>
>>> Am 13 Aug 2004 14:55 meinte John Lawson:
>>> > On Thu, 12 Aug 2004, Stan Barr wrote:
>>> > > Hi,
>>> > > ben franchuk <bfranchuk_at_jetnet.ab.ca> said:
>>> > >> Stan Barr wrote:
>>> > >>> Work is still in progress. Shizuka University in
>>> Japan recently
>>> > >>> demoed
>>> > [snippage]
>>> > >> What is too slow. Paper Tape is slow. :)
>>> > > They don't say how fast, but imagine how long it would
>>> take to read
>>> > > 2000Gb at paper tape speeds :-)
>>>
>>> > No need to imagine - Calculate:
>>>
>>> > Lets say that the Paper Tape is in ASCII format, then each
>>> > character is a Byte - and that the Reader is a fairly
>>> advanced optical
>>> > device running at a conservative 1200 bytes per minute.
>>>
>>> > 2000 GB (2 TB) is 2*10^12
>>>
>>> > so (2*10^12)/1200 = 1.66666667*10^9 minutes to read 2 TB
>>> > /60 = 27,777,777.8 hours
>>> > /24 = 1,157,407.41 days
>>> > /365 = 3171 years
>>> > presupposing a Really Good reader that could operate
>>> that long w/out
>>> > any maintenance or downtime.... probably Sellam has a
>>> couple of these
>>> > on his Shelves.
>>>
>>> > NOW: 10 KB of 5-mil thick punched paper tape on a
>>> 3/4-inch hub
>>> > with a punch width of .060 and an inter-character width
>>> of .060 makes
>>> > a diameter of.... oops my brain just exploded - sorry.
>>>
>>> > But damn! that would be an impressive wheel of paper!!!!
>>>
>>> Nowwaitaminute.... Impressive Paper roll? that reminds me
>>> of news paper printing, and AFAIR they use speeds of above
>>> 40 km/h (25 mph) at at the press in one newspaper here in
>>> Munich (Sueddeutsche Zeitung)... With way less quality
>>> paper than paper tape used to be.
>>>
>>> Now .. let's for now assume a bit hole is about 1 mm in
>>> diameter, and the gap between is of equal size, thus one
>>> byte every 2mm.
>>> now, assumeing a speed of 40 km/h this gives 40,000,000/2
>>> Bytes/h or 20 MByte/h transfer rate (or with around 333
>>> KByte/min or 5 k/s almost 300 times the speed you assumed).
>>> The problem is still the paper transport, not optical
>>> sensing, since even an 8 Bit controler is be able to shovel
>>> awy the data.
>>>
>>> 2*10^12/2*10^7
>>>
>>> ... gee that's easy to cancel down ...
>>>
>>> 1*10^5 hours
>>> or just about 14 Month
>>>
>>> Hey, that's fast!
>>>
>>> Average access time of just 7 Month - large enough paper
>>> roll assumed.
>>> (2*10^12*2^-3m = 4 mil km, or 11 times the distance
>>> eath/moon - hey, waitaminute, this means our reader can eat
>>> it's way to the moon in just a month :)
>>>
>>> Gruss
>>> H.
>>> It's your fault, John, you got me going :)
>>> --
>>> VCF Europa 6.0 am 30.April und 01.Mai 2005 in Muenchen
>>> http://www.vcfe.org/
>>>
Received on Fri Aug 13 2004 - 15:09:56 BST