System Expansion
The journey continues – the next task after having something printed was to put my original ZX Interface 1 into operation. It was part of the official ZX Spectrum Expansion System, which consisted of the ZX Interface 1 itself, a ZX Microdrive, network cabling and a software bundle on Microdrive cartridges.
Shortly after the purchase of this setup in 1985 I bought some additional blank Microdrive cartridges.
ZX Net
Beneath being the hardware for operating ZX Microdrives the ZX Interface 1 sports a non-standard 9-pin serial connector to drive 3rd-party serial printers. And it introduced the Sinclair version of a Local Area Network: ZX Net. Now that I had two Interface 1 I were able to set up my first official high-performance serial Sinclair-ZX-Spectrum-network – in the year 2017!
I connected both Interface 1 with the network cable (see red arrows in the picture above) from the Expansion system pack, switched on both ZX Spectrum and typed in the „Roots“ program from Chapter 7 of the „Microdrive and Interface 1“ manual. It’s a little demonstration of how to setup the network in general (i.e. assign network station numbers) and how to send and receive (program) data.
It worked out of the box – so at least the networking part of both Interface 1 seemed to work properly. Another test showed that both of them recognized a attached (empty!) ZX Microdrive by spinning up it’s motor after entering a CAT 1. Marvellous!
Sinclair tried to set the standard for networking and „mass storage“ with the ZX Interface 1 inside the Sinclair ecosystem – so even the more business orientated successor (the Sinclair QL) sported both components. But they failed: While the ZX Net option was indeed used sometimes both the Sinclair ZX Spectrum and the Sinclair QL quickly got 3rd party industry standard floppy disc interfaces (for those people who were able to afford them).
Related Links
ZX Net
ZX Interface 1
ZX Microdrive
ZX Spectrum Expansion System
Sinclair QL