Punch Cards.

[Bill Davidsen]

Ed Gurski wrote:
> On Fri, 2008-04-04 at 02:01 -0400, fedora-list-request at redhat.com wrote:
> 
>> On Thu, 2008-04-03 at 23:44 +0100, Nicholas Robinson wrote:
>>> On Thursday 03 April 2008 23:06:44 Tim wrote:
>>>> On Thu, 2008-04-03 at 10:25 -0600, Robin Laing wrote:
>>>>> It was nice to see the TTY there.  I remember having a Star Trek
>>>>> program on paper tape.  Let it roll down the outside of the residence
>>>>> building at school.  It was over 10 stories long.
>>>>>
>>>>> We were the lucky ones in the second year.  We had a TI terminal that
>>>>> had a cassette tape in it.  No more punch cards or paper tape for
>>>>> us.  :)
>>>> I would have thought paper tape to be more reliable than plastic tape.
>>>> No stretching, no striction, reversable and relocatable for a re-read,
>>>> repairable by your engineers when someone breaks it, duplicatable
>>>> through various direct methods without degradation of data.
>>>>
>>> Yes, we had a very, very short-lived trial with cassettes for exactly the 
>>> reasons you mention. We went on to these new-fangled floppy discs with a huge 
>>> capacity of just over 100k bytes. We carried on using paper tapes for a 
>>> while, just to be sure. We were real men though and had to repair our own 
>>> tapes. It was tough in those days.
>>>
>>> The typical session started with bootstrapping RIM into the PDP 8e and then 
>>> loading the BIN loader off paper tape. Assuming you didn't make a mistake 
>>> hand-loading the 30odd 12 bit instructions in the RIM loader and the paper 
>>> tape didn't jam/fall out of the reader/stop for no apparent reason, you were 
>>> in business and could then load another paper tape with something more 
>>> interesting on it, like BASIC or Algol or an assembler (subject to the 
>>> jams/falls/stops noted before). If the optical paper tape reader (300 or so 
>>> cps) failed then we had to resort to the old teletype reader which was rated 
>>> at 10 cps, but always seemed slower. Even with only 8k core memory, it still 
>>> took a long time to load a big programme.
>>>
>>> Ah, how the younger ones on the list must be enjoying reading about the lives 
>>> of the when-we's.
>>>
>>> Nick
>>>
>> Ah, yes... I used to dread the infamous tape break.  We even had the
>> little template thingy that you could put the two ends into to help get
>> the magic tape on the right way.  But I was invariably too clumsy and
>> ended up with one of those dreaded wrinkles that would slide the tape
>> sideways at the most inopportune time (like after 3/4 of a long program
>> had been read in.)  So I would usually patch the the tape, then dupe it
>> so I had a "real working copy" because the duplicator would deal with
>> the wrinkle much better (but more slowly if possible).
>>
>> Regards,
>> Les H
>>
> 
> Remember the rewind and stretch tape in the (then new) Univac VI c Servo
> tape drives! 2400 ft of tape rendered useless at 1200 BPI!!! Then the
> Univac 1050 was a transitional machine with mostly transistors but still
> some tubes. Loading a program required you (the programmer) to define
> which Exec was going to be used (there were 3 - Console, Canadian and
> the third escapes me --- obviously the last was hardly used....
> 
The juxtaposition of Fibonacci numbers, tape stretching, and punch cards 
reminds me of the original GE-605 mainframe I programmed "back when." 
The 605 was the military version of the GE-635, and had extended 
hardware, was slightly faster, and could be put in a tractor trailer and 
driven around. It had Potter tape drives, which were chosen because they 
could be serviced from front only and bolted to a wall. Like most 
drives, they had deep vacuum tanks for tape loops.

I wrote a program to calculate Fibonacci numbers and write tape blocks 
of that length, such that they went from very large down to one work, 
then back to very large. If you positioned the tape in the middle (small 
records), and did a FSR (fwd space record) one, then back two, then 
forward three, etc, at some point the motors would turn in the opposite 
direction and break the tape. Later conversion to mylar tape changed 
this to stretch rather than break.

The program was called "buster," for obvious reasons.

We also used to wait for the operators to put a cup of coffee on the top 
of the chain printer while removing output, then send the "raise hood" 
command and watch them scramble. Innocent days, computers were fun.

-- 
Bill Davidsen <davidsen at tmr.com>
   "We have more to fear from the bungling of the incompetent than from
the machinations of the wicked."  - from Slashdot