"Hugo Cornwall "The Hacker's handbook"" - читать интересную книгу автора

for that, before you even think of hooking it up to a modem.)
ost professional data services assume the user is viewing on an
80-column screen; ideally the hacker's computer should be capable of
doing that as well, otherwise the display will be full of awkward
line breaks. Terminal emulator software (see below) can some- times
provide a 'fix'.
ne or two disc drives are pretty helpful, because you will want
to be able to save the results of your network adventures as quickly
and efficiently as possible. Most terminal emulators use the
computer's free memory (i.e. all that is not required to support the
operating system and the emulator software itself) as store for the
received data, but once the buffer is full, you will begin to lose
the earliest items. You can, of course, try to save to cassette, but
normally that is a slow and tedious process.
n alternative storage method is to save to a printer, printing
the received data stream not only to the computer screen, but also on
dot matrix printer. However, most of the more popular (and cheaper)
printers do not work sufficiently fast. You may find you lose
characters at the beginning of each line. Moreover, if you print
everything in real-time, you'll include all your mistakes, false
starts etc., and in the process use masses of paper. So, if you can
save to disc regularly, you can review each hack afterwards at your
leisure and, using a screen editor or word processor, save or print
out only those items of real interest.

Serial Ports

The computer must have a serial port, either called that or marked
RS232C (or its slight variant RS423), or V24, which is the official
designator of RS232C used outside the USA, though not often seen on
micros.
The very cheapest micros, like the ZX81, Spectrum, VIC20, do not
have RS232C ports, though add-on boards are available. Some of the
older personal computers, like the Apple or the original Pet, were
also originally sold without serial ports, though standard boards are
available for all of these.
You are probably aware that the RS232C standard has a large number
of variants, and that not all computers (or add-on boards) that claim
to have a RS232C port can actually talk into a modem.
Historically, RS232C/V24 is supposed to cover all aspects of
serial communication, including printers and dumb terminals as well
as computers. The RS232C standard specifies electrical and physical
requirements.
Everything is pumped through a 25-pin D-shaped connector, each pin
of which has some function in some implementation. But in most cases,
nearly all the pins are not used. In practice, only three connections
are essential for computer to modem communication:

Pin 7 signal ground
Pin 2 characters leaving the computer