9 Mar
2002
9 Mar
'02
3:59 a.m.
Lawrence LeMay wrote:
The TTY is the LOW speed punch/reader ... 10 CPS.
The high speed reader is 300 CPS for the PDP-8.
The problem with paper tape
on the PDP-8 at least is that you had to read a character at a
time. Read char... process ... read. This meant the paper tape
had to stop the tape on every character. Reading the tape is
not the problem ... stopping was.
--
Ben Franchuk - Dawn * 12/24 bit cpu *
www.jetnet.ab.ca/users/bfranchuk/index.html
A low speed punch 10 cps vers a high speed punch
50 cps could be a important cost factor. Now if you
had black paper tape one could zap out the holes
with a laser giving you a very high speed punch.
Since the punching speed does limit paper
tape to a practical limit of about 8kb was there
any really large paper tape programs? 4K focal on
a TTY was as long a program that I ever loaded from paper
tape ... 20 minutes.
Well, a good optical reader can read 400 characters per second. Correct me
if i'm wrong, but that seems like 4096 bytes takes 10.24 seconds to read
in. Assuming its not a 30 year old tape that vaporizes at that speed ;)
-Lawrence LeMay