On 2016-Apr-23, at 10:06 AM, Chuck Guzis wrote: > On 04/23/2016 05:41 AM, Noel Chiappa wrote: >>> From: Brent Hilpert >> >>> I'd say the 74181 (1970) deserves a mention here. Simpler (no >>> register component, ALU only) but it pretty much kicked off the >>> start of IC-level bit slicing. > > I recall reading about the 74181 introduction back in the day--it > created great excitement and speculation about how far the industry was > from a computer-on-a-chip. I think I still have a couple of the things > in my hellbox.
In 1972 or 1973 one of Radio Electronics or Popular Electronics had a construction article for the E&L Instruments Digi-Designer. If you recall, the Digi-Designer was essentially a vehicle for E&L's new plug-in breadboard. For those younger, yes, -those- plug-in breadboards, that are still the most prevalent hardware prototyping/educational technique today. AIR, the 74181 was featured as an experiment to wire up on the Digi-Designer in that article. > In the day, I'm not certain that TTL had the edge on integration, > however. It always seemed that DTL and RTL had the edge in complexity. > Before the 181, I was playing around with the RTL 796 dual full adder > and an 8-bit Fairchild DTL memory--IIRC the latter used a 7V clock. I think TTL was quickly on par for density with DTL & RTL and overtook them by the late 60s. I have 7490s (decade counter) from late-1966 and early-1967, and many TTL MSI functions were there by 1969. The 7484 (16-bit memory) is listed in the TI 1969 TTL databook. RTL was passe by then and DTL was heading that way. I don't think DTL got any more complex than such as the 8-bit memory you mention, at least in the main. I was surprised by the early date code on the 7490s when I ran across them in a piece of test equipment. > The interesting thing was that there seemed to be a distrust of LSI > chips early on. I recall working on a project around 1973, where the > lead engineer preferred to design his own UART from SSI rather than use > one of the new UART chips. > > --Chuck > > > >
