What does ULA stand for?

Frequently Asked Questions about the Sinclair ZX81
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What does ULA stand for?

Post by TheZuke »

Since rediscovering the ZX81 family, I was curious what was meant by the ULA integrated circuit.

Well, as they say, GIYF, Wikipedia shows it to mean "Uncommitted Gate Array" or in other words, an IC with a bunch of logic gates that can be configured by connecting (or disconnecting) paths between the various gates such as PALs (Programmable Array Logic).

Anyway here is the link:

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Re: What does ULA stand for?

Post by Bukster »

I think it's Uncommitted Logic Array. So your link was close to the mark.
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Re: What does ULA stand for?

Post by 1024MAK »

Although Sinclair documentation called it the Sinclair logic chip, ULA does mean Uncommitted Logic Array.
With these, all the semiconductor structures are already designed and defined by the chip manufacturer. But the final top metal interconnect layer can be designed by the customer (meaning the industrial buyer, that is for example, Sinclair) to suit their application. The chip manufacturer then adds this custom metal interconnect layer making the chip a semi-custom design.

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