80-Bus News


November–December 1984 · Volume 3 · Issue 6

Page 6 of 55

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 controlling software.

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 bought Pascal.

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 July/​August issue.

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 ____-_____ and join the club.

Yours truly, GS Chatley, Cheshunt, Herts.

No Improvement

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 has noticed?

This time as an act of my good faith [Ed. – ????????] I have delayed sending my cheque until actually having received my full compliment of issues from last time.

Yours hopefully, J. Brown, __ _______ __., Didcot, Oxon. ____ ___.

[Ed. – the receipt of this issue (assuming it returns from the printer in a 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.]

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