What does ULA stand for?

Frequently Asked Questions about the Sinclair ZX81
Forum rules
This is designed to be a simple set of questions and answers - please no general chit chat in here - keep it focused to help new users!
Post Reply
TheZuke
Posts: 3
Joined: Mon Jul 29, 2019 8:04 pm

What does ULA stand for?

Post by TheZuke » Thu Aug 01, 2019 5:27 pm

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:

https://en.wikipedia.org/wiki/Gate_array

Bukster
Posts: 49
Joined: Wed Sep 12, 2018 9:44 am

Re: What does ULA stand for?

Post by Bukster » Sun Aug 04, 2019 6:10 am

I think it's Uncommitted Logic Array. So your link was close to the mark.

User avatar
1024MAK
Posts: 2532
Joined: Mon Sep 26, 2011 10:56 am
Location: Looking forward to summer in Somerset, UK...

Re: What does ULA stand for?

Post by 1024MAK » Thu Aug 29, 2019 11:25 am

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.

Mark

Post Reply