Versatile microcomputer
The System 80 com – puter, which is fundamentally a packaged Nascom -2; has been designed for flexibility, several new boards having been introduced. The main housing contains a racking frame which holds a mother board, a power supply, the c.p.u. board and up to four expansion boards. Provision is made for external connection to the boards and the computer has a g.r.p. cover with a keyboard cutout. A future expansion housing will accommodate a further five boards, mounted on top of the System 80 case. A programmable character generator board uses 2k bytes of static r.a.m. and can accept the Nascom blockgraphics ro m. The high resolution graphics operate on a cell structure consisting of 112 dots. Up to 128 cells can be produced in the 2k r.a.m. and each cell, once defined, can be displayed anywhere on the screen. A colour board offers high or low resolution for the three main television systems or an r.g.b. output. High resolution uses 6k of static r.a.m. and gives a choice of 16 colours. A dynamic r.a.m. board is available with 16, 32 or 48K bytes and has decoding, buffering and memory support. An input/ output board can accommodate three MK 3881 p.i.as, a MK 3882 counter-timer and a 6402 u.a.r.t. The fifth optional board, a floppy disc controller, can handle up to four Siemens double-density, double-sided 5 1 / 4 in drives using the 1791 i.c. Various link options permit single or double-sided and single or double-density disc to be used and the c.p.u. can be run at 2 or 4MHz. Nascom claim that the larger the system, the more competitive the price becomes. For example, with System 80 supported by 96K of r.a.m., a programmable character generator, a high resolution colour card, and a complete twin disc set, the cost is about £1,750. All parts can be supplied in kit form. Nascom Microcomputers Ltd, 92 Broad ‘ St, Chesham, Bucks.
–Wireless World May 1980
When Lucas Logic took over Nascom one of the projects under development was a new system using the NASBUS. This was a really hot topic of conversation in the Merseyside Nascom User Group, I remember! There was all sorts of speculation as to what might be happening.
Several new boards were in the process of being designed and adverts were placed with magazines, but the whole thing was cancelled and never reached production.
No technical details are known about System-80 other than these.
I’ve shamelessly taken most of this information from Richard’s excellent site at https://80bus.co.uk simply because it’s the only place I’ve been able to find it.
According to INMC news Issue 7, the RAM B board was part of the new System-80 system. This would make sense as it is obviously a big advance on the original RAM board.
The new power supply was to have been 5A rated.
The disk system would have stored about 280k per drive under CP/M
A programmable character generator, moving the Graphics ROM onto the new board and connecting it to the NASCOM-2. 2KB of RAM on board to give a resolution of 384×256. No details of how this was to be achieved in software.
Designed to be used with the above character generator, a new colour encoder board. To give 16 colours, split between foreground and background. Colour definition would have been on a 96×48 grid using 6KB of on-board RAM. Stated as being able to produce 256 colours, but it is not known how they would have achieved this.
When Lucas released their new floppy disk control board it was originally thought that it was actually the System-80 board design that had been resurrected. However it proved to be a brand new design.
nascom.info 