Some useful information about Bulletin Board Systems. By John Ilsley. This article will be of interest to
those of you that own modems. Those of
you that don't, then I hope that this
article will give you an incentive to
buy one.
This article is written around my own
experiences of modems.
Nearly all modems that you can buy will
connect to the BBC A, B or Master128
via the RS423 port. The Master128 can
also have an internal modem fitted.
But to date, I have heard of no one who
has this built-in modem, I have in it's
space my telephone.
The RS423 port will interface with a
modem's RS232 port with no problems.
You will find that all modems require
at least five connections. These are:
TX/SD (Transmit or Send data).
RX/RD (Receive data).
RTS (Request to send).
CTS (Clear to send)
0v line, or earth.
These are the five pins. The actual
pinout's can be found on page 240 of
the Master128 welcome guide or page 499
of the BBC B manual.
All computers can talk to each other,
It doesn't matter whether it is a PC,
BBC A or B, Master, Spectrum, Commodore
Atari, Amiga, Archimedes.
As long as you have the four main
essentials:
A computer, modem, software and access
to a phone socket. The rest is easy.
If you intend to call a bulletin board
system or BBS for short, you will first
have to select at your computer whether
you wish to call in viewdata or
terminal/scrolling. Viewdata will allow
only downloading, whilst scrolling will
allow uploading or downloading.
Uploading allows you to send a program
or a file from your computer's disc
drive to the BBS. Downloading allows
transfer of files from the BBS's disc
drive to you.
Viewdata has a word bit stop of 7E1 and
scrolling has a word bit stop of
normally 8N1.
You can dial to most boards at at least
300/300 bits per second (bps) or
1200/75bps. The first number is the
speed you receive the information at,
the second number is the speed you send
the information at.
Most times when you call a BBS, you
will select 1200/75 as this allows fast
frames and quicker downloading. Should
you wish to upload, you should call at
300/300. Very few modems can handle
75/1200, I have left this speed out.
When you first connect to a BBS, you
are more then likely to see a message
at the top of the screen saying
something like:
'Press Hash Press Return'
You must press your RETURN or enter
key. This key, although the code on
the BBC computer is CHR$(13), if you
are in Viewdata, is changed to
CHR$(95) If you are in scrolling, it is
left as CHR$(13).
This is how the BBS computer or host
computer tells whether you are calling
from Viewdata or Scrolling. After that,
you will be asked for your first and
last name, your location and a secret
password. You must always keep this
password secret. I will tell you about
the relevance of this later.
Some BBS's ask you to fill in a
questionaire when you first log on.
After this you will be presented with a
welcome page or main menu. This may
tell you when the BBS was last updated
and if you have any new mail and
whether the Sysop is in or out. The
Sysop is the person who is in charge of
the system. It is up to him/her to make
sure that your name, password and where
you are from are kept secret. He/she is
the only person who will see that
information.
You are then most likely see somewhere
on the introduction page, a '#' or
hash, this means press RETURN. You may
see the letter 'M' or '0', Press either
of these to get to the main menu. Once
on the main menu, you have a choice of
things to do.
A lot of BBS run on a hard drive, or on
silicon drives, these are extremely
fast, these BBS's have lots of money
and modems that can do speeds of up to
96000bps. At that speed, you get a
screen full of information faster than
you would if you catalogued a disc. It
is extremely fast.
The best modems I know about are most
Hayes compatible modems These use 'AT'
commands. For example:
ATZ will reset the modem.
ATPD0705753124 will pulse dial a number
(mine).
ATTD0705753124M1C1 will tone dial a
number, (mine again), send a carrier
and turn the modem's internal monitor
on if it has one.
I think a satisfactory Hayes modem is a
WS4000. This is very easy to use, and
operates with most software and can be
operated from basic.
You will need software to download and
upload files. I recommend the following
in order of preferance:
MODEM MASTER
COMMAND
Designer modem by Dataphone needs the
rom ZROMM and is a very good modem,
sadly I don't think they are produced
any more, they are well worth it if you
can get one. If you are in a basic
program and someone calls, you can
simply answer them without losing your
program. One modem to avoid is BT's own
modem, the DataChat1223.
Most new modems cost in excess of £150
for a simple 1200/75 300/300 modem.
Fine if you have the money.
However a second hand one will cost
about £25-£40. A new, high speed error
correction modem will cost in excess of
£400, £160 is a good 2nd hand price.
John Ilsley 27N.
PRESS BREAK