NC4016 – A Forth chip ahead of its time

As a trainee i had the privilege of working with a Novix NC4000 beta Board – It used a NC4016 Forth CPU that maintained separate code and stack space, making it incredibly fast. Allowing separate busses allowed the device to read memory on the same clock cycle as it updated a stack.

From memory, we used the board in an image processing lab, to allow researchers to perform viscosity measurements. Essentially, a video camera was focused on a very small tube as a material was flowed down the tube. The camera would detect when the flow passed two points, sometimes it took milliseconds, sometimes it took days.

I wish I had photos of the lab rig, it was particularly interesting, involving constant temperature water baths, forced flow control to ensure that the bath was at the required temperature, sensors everywhere and different samples.

Before the Novix rig, it was all controlled using Amstrad CPC464 computers. (Without the cameras).

I was lucky enough to score a STD bus version of the board. It contains 16k or 16 bit data memory, and 2k of 16 bit data stack, as well as 2k of return stack. It has cmForth in ROM. Communications is via a three pin molex connector (TX/RX/GND) [Flow control, where were going, we don’t need flow control]. The header provides access to the port B pins for parallel expansion.

NB4300 STD Forth board

On my never ending list of hobby projects, is to implement some type of disk controller for it, but I suspect that it uses a host base disk system, meaning that disk is accessed down the serial line connected to the host computer.

I have *no* idea what the jumpers on the board do – If anybody has any ideas I would really appreciate it 🙂

For archival purposes, I have included the dumps of the original disks that came with the Novix beta board, as well as the roms from the NB4300 board. This is an Intel Hex dump of the Roms.

The following files are the floppy disks that came with the Bets board – I combined them into a side by side view – One disk contained source, and the other disk contained shadow comments. briliantly clever for the time.

Sadly in this era of files that can damage computers, I can’t store disk images here – if you need them, just email me at

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