80-Bus News

  

July–August 1983, Volume 2, Issue 4

Page 10 of 55

The Nascom Card.

The Nascom card is most suited to the Nascom as the software is written with use under NAS-DOS in mind. Nascom tape versions are available, and I understand some form of software is to be made (or is) available for use under CP/M. The software provided (on NAS-DOS disk) is exchangeable to tape on request is in the form of an extension to the Nascom Basic, and provides a number of useful commands. Being page mode memory mapped no provision need be made within the memory map. The NASIO signal is provided.

The Climax Card.

The Climax card is equally suited to the Nascom or Gemini but the software is available only on disk in Gemini formats and aimed at use with the Microsoft MBASIC and hence, implies the use of CP/M. Full listings of the colour driver primitives are supplied and it wouldn’t be too difficult (more tedious) to convert them for use with Nascom Basic or ‘stand alone’ machine code subroutines. Being port addressed no provision need be made within the memory map. The NASIO decode signal is provided.

DOCUMENTATION.

The Pluto Card.

A slim, ring bound volume is provided with the Pluto, and introduces the features of the Pluto card, fitting to the system, an explanation of the preprogrammed board functions and a couple of demo programs. Although thorough and well written, I found something indefinably wrong with this manual, I found it extremely difficult to understand and yet it was written clearly enough. It took several goes through the book to grasp an understanding of the Pluto card from the manual. References to command types were in alphabetical order which didn’t help as I wasted considerable time searching for control codes by the obscure alphabetical labels given to them instead of being able to spot them instantly. In the end I rewrote the command lists in function order to make them understandable.

No circuit diagrams were supplied and the technical description was brief. I found it helpful to draw a block diagram of the card from what description there was and what I discovered in use.

On a couple of occasions I resorted to phoneing IO to clarify points, on each occasion I was answered by a telephone answering machine. Now as a rule I hate telephone answering machines, but they usually give you the option of leaving a message to ring back or saying something rude about answering machines. This telephone answering machine was exactly as described, it answered the phone, told me no-one was around and then rang off. Not very helpful at all!!

In the end I had so much trouble thumbing through the manual to find things that I decided to write a set of straight forward driver routines linkable from MBASIC in the same manner as the Climax routines. I got some way with this, but as yet have not finished them.

The Nascom Card.

In contrast to the IO manual, the Nascom manual is a fat tome, bound in a ring folder of Lucas green. Everything was explained in exhaustive detail and was very clearly written. All the software functions were well explained with numerous examples. Circuit diagrams were provided and a fairly thorough circuit description was in the manual. As the Nascom card has little computing power of its own, being confined to the line and frame generation and memory mapping of the 6845 video controller chip, all functions such as line drawing


Page 10 of 55