vLA1 – A Sinclair Interface 1 ULA replacement

The original ULA has an unfortunate history of being prone to spectacularly overheat and fail without warning, leaving an unsightly crater in the Interface 1 plastic case. Because of this, and due to the original ULA now becoming hard to find, the vLA1 project was born.


The vLA1 is a pin-for-pin functional replacement for the Sinclair ZX Interface 1 ULA using a modern programmable logic array. The vLA1 provides full support for the Microdrive, RS-232 and Sinclair Network as in the original ULA.

The vLA1 comes in a 40 pin DIL package suitable for soldering into the Interface 1 PCB. A word of caution however, due to a lack of room within the Interface 1 case, the original ULA will need to be desoldered/removed and the vLA1 installed in its place. There is simply not enough room for a socket. Have a look through the install guide and you should get a good idea of what’s involved.


An Interface 1 PCB ready for a new vLA1!


Installed and ready to go

To get your vLA1 head along to my new store.

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