Date : Tue, 15 Jun 1999 15:59:10 +0100 (BST)
From : "Andrew Benham" <adsb@...>
Subject: Re: BBC 8271 commands
Looking at the BBC B circuit diagram and the Intel 8271 data sheet,
the address mapping is:
Read Status write to FE80
Write Command read from FE80
Read Result read from FE81
Write Parameter write to FE81
Write Reset write to FE82
Write Data write to FE84
Read Data read from FE84
Because of the BBC address decoding, multiple addresses can be used
for each of the above. A full BBC B simulation should probably handle
these other addresses, just in case.
Main Address Other working addresses
Andrew Benham adsb@...
Nortel Networks Plc, London Road, Harlow, Essex CM17 9NA, United Kingdom
Tel: +44 1279 402372 Fax: +44 1279 405746
I speak for myself, my views are not necessarily the views
of Nortel Networks or any other corporation.