The SCROM

I suspect very few people know about this “Not Quite a Signetics product”. The inventor of the term surely was the late Jerry Lawson in about 1969. Larry should have been a standup comedian because he was ON most of the time. Joking, laughing and clapping his hands. He was a big guy, six foot plus.  He was in the video game business from its inception and was an expert on this subject and most anything else electronic, fascinated with everything electronic from when he was a boy..

Oh, almost forgot the SCROM. the Scratchable Read-Only-Memory.  Larry was head of a Signetics project to develop what later was labeled the Signetics 8223 PROM, a “Programmable Read-Only Memory“. This was a 32 X 8  (32 bytes of 8 bits wide) ROM that you programmed with a PROM Programmer*. The little PROM served as a small amount of non-volatile data storage. It was used in teletype machines, power plants and many other systems needing a small, permanent data storage. In fact, the cellular phone was birthing about then and eventually used the Signetics 8223 (and other similar devices) for storage of the phone number and other data pertinent to a particular phone. In cellular circles, it was now called a NAM (Number Assignment Module) and many were produced, programmed and placed in cell phones until they were designed out when EPROMs (Eraseable Programmable Read Only Memories) arrived. They held much more non-volatile storage, were tiny and could store the phone’s operating system, the NAM information and whatever else was needed.

Again, I digress. The 8223 contained 256 fuseable links which could be burned open to produce either a one or a zero binary bit. The fuse had to be developed whereas the rest of the integrated circuit was standard. Until the fuse (and a programmer) was developed, a technician could program a prototype part by scratching the fuse links open manually with a pick. It was a big job, but the part was useable for prospective customers to use in their prototypes. Jerry called it a SCROM and I believe it was conceived in his fertile brain. And most probably the moniker WOM too. It was just there one day.  ( I am not sure of the exact period when Jerry was employed by Signetics and if he was there at the WOM conception.)

Jerry passed on in April, 2011, at the age of 70, a genuine loss. I wish he could be here to enjoy the pureification of the WOM’s history. That would be a kick. I’ll find an article on him and link here.

*I designed a programmer (PR23) for the 8223 and left Signetics in 1969 to start a small company to produce it (Curtis Electro Devices, Inc.). But that’s another story.

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