claim responsibility for this is beyond me. It consists of the lower 7
address bits, the data bus, reset line, interrupt request, 2 MHz clock, Read/
Write line and a select line. All the lines are unbuffered, and are connected
directly to the 6502 wherever possible. Incidentally, there is less buffering
on a BBC than on a Nascom 1.
The 1 MHz bus may be thought of as a set of uncommitted ports, and the
Tube as a way of talking to the BBC, when the BBC can be bothered with you. A
second processor for the BBC uses it to talk to the world. Imagine a Gemini
Ivc/SVC with optional networking and disk controller.
Perhaps if you were to tell us why you want to interface a computer with
a toy, more information could be provided. Try the BBC advanced user guide,
as this should be able to help you considerably, assuming that you can write
On the subject of BBCs, I would like to say that Dave Hunt put his
comments on BBC “BASIC” very well, and the only fair criticism that I feel
could be made of his article, is that he didn’t criticise the BBC “BASIC”
enough. Perhaps Mr Hellen would be able to appreciate this more if he had
Finally, in my last letter, I suggested putting up the subscription to
maintain the quality of 80-BUS News. As I have just paid my subscription, I
realise that I am clear of this prospect for another year. However, I still
feel that this is an appropriate step, considering the reduced length of the
All the usual garbage, Kevin Wood, Canterbury, Kent.
More on BBCs
I am writing regarding Chris Hellen’s letter on BBC BASIC. I have used
this system on my BBC/TORCH system and with dual disks and 64K of memory it
serves all my needs.
However, I still have my old CRASH AT 2MHz NASCOM 2 with buit-in amnesia
and have been having thoughts that a transfusion via the RS232 port would be a
better bet than the bus/tube system proposed, as timing will be difficult.
If anyone wants to join the insanity trail, please ring 0992-25386 and
join the club.
Yours truly, GS Chatley, Cheshunt, Herts.
Thank you for publishing my letter last year, it is a pity that you felt
unable to answer it. [Ed. – see Vol. 2, Issue 4, page 4 where Mr Brown
complained about a distinct lack of 80-BUS News, but kindly enclosed his
resub. all the same!!]
This year I received a subscription reminder in April, dated May/June,
whereas the last copy of last years subscription did not arrive until
December. Is there any hope of improvement or are you assuming that no one
This time as an act of my good faith [Ed. – ??7227??] I have delayed
sending my cheque until actually having received my full compliment of issues
from last time.
Yours hopefully, J. Brown, 21 Mowbray Rd., Didcot, Oxon. OX11 8ST.
[Ed. – the receipt of this issue (assuming it returns from the printer ina
reasonable time) should put us only half–>one issue in arrears. As for 1985,
you will have noticed that for some time the subscription has been stated to
be for 12 months, and not for a specific number of issues.]