Date   : Thu, 09 May 1996 14:46:11 +0200
From   : deweger@... (Mark de Weger)
Subject: Re: How to make Beeb 2 PC cable

Hi all again,

Thanx a lot for the many reactions to my question about
making up a cable for BBC <-> PC communication. Sorry
for bothering you again with a lengthy mail about this
subject, but I just need some confirmation about the
procedure to be followed. (I'm a rather uncertain type
of person, you see :)

I will wait for the persons who have said they will look
up the details of pin connections. However, do you think
the following procedure would be the easiest to make
a cable? (Ease of making it is rather important for me,
because I have very little hardware knowledge and have
only soldered once in my life.)

1. Buy a PC to PC serial cable. This one has probably already
   wired the different PC ground pins wired together at each
   end, so I don't have to worry about that. (Or am I wrong
   in assuming so?)

2. Remove one of the sockets from the serial cable carefully
   writing down to which pin each wire is connected.

3. Get a 5-pin domino DIN socket.

4. Connect the wire that used to be connected to the removed
   socket's CTS to the DIN socket's CTS.
   Same for RTS, Data In and Data Out.

5. Transfer Killer Gorilla!

Now my questions:

1. Does the above procedure seem correct?

2. The new wire-up would be:

   PC:                              Beeb:

   ground pins wired together        ground pin
   CTS      <--------------------->  RTS
   RTS      <--------------------->  CTS
   Data In  <--------------------->  Data Out
   Data Out <--------------------->  Data In

   Is this correct? (In particular: given that the Beeb's got
   five pins and four of them are non-ground, there's only
   one ground pin left. I cannot wire this up to something.
   Or do I have to connect it to the PC's ground pins?)

3. Is TxD/Transmit the same as Data Out?
   Same for RxD/Receive and Data In?

Well, if you've read this far you deserve Mark's Honorable
Reading Award, which you are granted hereby. And I'll keep
you posted on where you can find the files I am going
to transfer (provided I succeed).

Cheers,
Mark.