Failing memories indeed. I worked for CDC Sunnyvale Ops back in the early 1970s and part of that time I was briefly working on the FTN (aka Fortran) compiler, Pass 1. The regular floating point on the 6600 was 60 bits as the word size on the computer was 60 bits.
The failing memory part — I believe that the FTN compiler itself implemented double-precision 120 bit floating point that was a slight sacrifice of screaming performance (at the time) for higher precision. I think this was FTN’s type G floating point. So, this floating point did not have 120 bit registers but rather treated two 60-bit words each holding half of the floating point double-precision number. Also the CDC 6600 was released in 1964. SN1 of the CDC 6600 was originally sent to Los Alamos labs but retired to Sunnyvale when I worked there (’72-75) and it was our main 6600 used by the FTN compiler project. Of course we had at least once each of all the 6000-series computers as well as a 7600. 73, phil, K7PEH > On Apr 13, 2018, at 12:48 PM, brian <[email protected]> wrote: > > My failing memory seems to recall that the CDC6600 used 60 bit math for > floating point single precision operations. > > https://en.wikipedia.org/wiki/CDC_6600 seems to confirm that. > > They were great machines, till the 7600 then the Cray computers showed up... > > It was interesting to bring these machines to their knees by physics > calculations that took days to run. They had to be run on weekends to keep > the rest of the lab happy. > > 73 de Brian/K3KO > > On 4/13/2018 18:06 PM, Fred Jensen wrote: >> We already did, in the later 70's. It ran on a CDC6600. We used it for >> guidance analysis and trajectory planning/simulation for the Apollo >> missions. FORTRAN IV, double precision FP words. >> >> 73, >> >> Fred ["Skip"] K6DGW >> Sparks NV DM09dn >> Washoe County >> >> On 4/12/2018 11:10 PM, Martin Sole wrote: >>> >>> When are we going to see 128 bit OS's :) >>> >>> Martin, HS0ZED >> >> ______________________________________________________________ >> Elecraft mailing list >> Home: http://mailman.qth.net/mailman/listinfo/elecraft >> Help: http://mailman.qth.net/mmfaq.htm >> Post: mailto:[email protected] >> >> This list hosted by: http://www.qsl.net >> Please help support this email list: http://www.qsl.net/donate.html >> Message delivered to [email protected] >> >> --- >> This email has been checked for viruses by AVG. >> http://www.avg.com > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:[email protected] > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Message delivered to [email protected] ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [email protected]
