and comprehensive programming interface to the operating system to facilitate
sophisticated applications programs. The SBIOS for Nascom has been implemented
via Al1Boot (mentioned above) that enables the disk drives to be configured under
software control. Thus almost any legal combination of 5" and 8" drives with
Nascom and Gemini(GM809) FDC cards and format (including the ability to use 48
tpi formatted disks on 96 tpi drives) can be catered for and reconfigured, at
will, while the system is running. The system can be run (although with a couple
of inconveniences) using the normal Nascom 16*48 display. However facilities for
a Gemini IVC and/or serial console are provided as are "hooks" to enable a Lucas
Logic AVC, or other CRT or keyboard of the user’s choice, to be used.
The printer can be software configured to use either the PIO (for a Centronics
type) or the UART (serial).
AliBoot sits at F000 – F7FF and RAM is required from FCOO for the SBIOS and F800
if Nascom video is used (can be changed on booting to any other address to which
the VRAM select is decoded). A minimum of 48K (60K is more suitable) RAM is
required below F000 and at least one disk drive (two is more sensible) with at
The Gemini version will be essentially the same except that it will be totally
RAM based (and with about 1K extra RAM at the top end of the memory map), the
Gemini boot ROM paging out after loading, and the Nascom video option will
obviously not be possible.
(Many thanks to Lucas Logic for their heip with 5.25" disk drives, by the way,
and also to Dave Hunt at Henry’s for patiently answering countless queries.)
About two years the UCSD p-System Users Society (USUS) was set up in the USA,
followed shortly by USUS(UK) over here. They have a large library of programs
(about 20 single density 8" disks’ worth) in various formats available for the
cost of the media and copying.
They also organise two full-scale conferences (usually at a University) every
year and distribute a Newsletter rather like this full of technical tips and
reviews of the latest aplications packages.
They can be contacted via:
Membership Secretary USUS(UK)
The Open University
How to get it
IT almost forgot (he said lying through his teeth) you can buy the Nascom
implementation (and soon Gemini/Galaxy/Quantum versions) from me, see my Ad. in
this mag. Alternatively hassle your Nascom/Gemini dealer and tell him/her to
order one thousand copies from me as soon as possible if they don’t want to be
left out of the rush.