write-only memory
write-only memory
(jargon, humour)Out of frustration with the long and seemingly useless chainof approvals required of component specifications, duringwhich no actual checking seemed to occur, an engineer atSignetics once created a specification for a write-onlymemory and included it with a bunch of other specifications tobe approved. This inclusion came to the attention ofSignetics management only when regular customers startedcalling and asking for pricing information. Signeticspublished a corrected edition of the data book and requestedthe return of the "erroneous" ones. Later, around 1974,Signetics bought a double-page spread in "Electronics"magazine's April issue and used the spec as an April Fools'Day joke. Instead of the more conventional characteristiccurves, the 25120 "fully encoded, 9046 x N, Random Access,write-only-memory" data sheet included diagrams of "bitcapacity vs. Temp.", "Iff vs. Vff", "Number of pins remainingvs. number of socket insertions", and "AQL vs. selling price".The 25120 required a 6.3 VAC VFF supply, a +10V VCC, and VDDof 0V, +/- 2%.