NASCOM2

Nascom2

These uses a Z80 CPU

See:-

http://ccgi.dougrice.plus.com/cgi-bin/wiki.pl?Nascom_2_Notes

The NASCOM 2 site is: http://www.nascomhomepage.com/#TheNascomRepository

I found a picture of my Nascom 2 from about 1984.

When I brought my Nascom 2 it came with the 16K memory card.

This had slots for 32K and people were adding another row or chips on top of exiting chips with the data in and out pins bent out.

I brought a second hand 8 inch floppy disk drive from Display Electronics.

Wireless World had a design that used the Western digital 1771 Disk controller chip.

Eventually it could read and write 60 out of the 80. tracks.

A 6116 2K ram memory chip had a switch on the R/W wire so you could save to it when presses, and it has a Ni-Cad battery backup.

Enough code to emulate the C and I instructions allowed specific sectors to be copied to and from floppy disk.

This code was run from a 6116 2K RAM chip. This chip had a Battery Back up circuit using a NiCad battery and a switch on the RW line to disable unplanned writes.

So a bit of paper with the sectors and addresses recorded where the programs were stored.

Later the first sector stored a program and the list of files, and you could select and load a program.

It was a lot quicker to use than the cassette player.

Sometimes you had to reload the 6116 ram chip from a cassette tape was required as the Ni-Cad only lasted about a week.