A patch was sent to Voyager 2 yesterday

Univac’s Fortran V was just their version of Fortran 66 w/extensions (like everyone else.) Athena Fortran was a third-party compiler that accepted the same language, plus added structured programming constructs and other features. I may have an Athena Fortran manual laying around somewhere, as I helped some people convert off of it. I know JPL also used Athena Fortran quite heavily. In fact, I seem to recall the guy who supported Athena was in Pasadena. There were only a handful of sites around the world who used Athena. So he never did upgrade it to be Fortran 77 compatible.

You are correct that Univacs follow-on was called ASCII Fortran - which did conform to Fortran 77. It used 9-bit ASCII characters, whereas when programming in Fortran V (Fortran 66), Hollerith constants provided 6-bit Fieldata characters. It was a major conversion issue. Some developers refused to port their codes to the newer ASCII Fortran until the machine was literally pulled from the machine floor. Then they were forced to move their codes to VAX, Cray, or whatever else was available.

I used a univac in the mid 1970s, but I had forgotten this detail. It was a 36-bit word addressable machine, so storing four characters per word would have made it easier to port to/from IBM machines, PDP-11s, and other computers that stored four characters per fortran integer. I used the compiler that stored 6-bit characters, I don’t think I used the compiler that stored 9-bit characters.

I also used a DECSystem-20 at the same time, and it was also a 36-bit word addressable machine. However, the fortran compiler on that machine stored five 7-bit ascii characters in each word, ignoring one bit in each fortran integer which was often used by the programmer for some other purpose. It was sometimes a chore to convert code to/from IBM machines because of that, and many converted programs just stored four characters, effectively wasting 8 precious bits per integer word.

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A descendant of the Ascii Fortran that @wspector mentioned is currently available from Unisys. They provide a ClearPath OS VM hosted on Windows to allow running Ascii Fortran. I do not know if anyone has actually installed and run the VM.

Believe me or not (after all I am a quiche eater), we could have save a lot of time (to eat more quiche and program in Fortran), by simply reading that fun and famous text:
Ed Post, “Real Programmers Don’t Use PASCAL”, 1982-83.

Some of the most awesome Real Programmers of all work at the Jet Propulsion Laboratory in California. Many of them know the entire operating system of the Pioneer and Voyager spacecraft by heart. With a combination of large ground-based Fortran programs and small spacecraft-based assembly language programs, they are able to do incredible feats of navigation and improvisation-- hitting ten-kilometer wide windows at Saturn after six years in space, repairing or bypassing damaged sensor platforms, radios, and batteries. Allegedly, one Real Programmer managed to tuck a pattern matching program into a few hundred bytes of unused memory in a Voyager spacecraft that searched for, located, and photographed a new moon of Jupiter.

All is said in one paragraph.


Should note that is the slightly more politically correct version of Ed Post’s original usenet version.

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The version I actually read is: https://justine.lol/dox/pascal.txt
Is it the original?
(I thought it was better to post a PDF version)

Although it appears to be, it isn’t. Seems to have the Datamation edits in it.

Look for one that refers to the Russians as “Russkies”, rather than “cosmonauts”. :smile:

It might be this one:

which is followed by the text “Real Programmers Don’t Use Fortran, Either!” (but “machine Code. Raw, unadorned, inscrutable hexadecimal numbers. Directly.”)

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Many people are fascinated by V’GER’s computers:

6 months of debugging and workaround, but they did it! Real Programmers… :champagne:

In fact, it is not totally finished as they still need to restart two other instruments.



While Voyager 1 is back to conducting science, additional minor work is needed to clean up the effects of the issue. Among other tasks, engineers will resynchronize timekeeping software in the spacecraft’s three onboard computers so they can execute commands at the right time. The team will also perform maintenance on the digital tape recorder, which records some data for the plasma wave instrument that is sent to Earth twice per year. (Most of the Voyagers’ science data is sent directly to Earth and not recorded.)

Interesting, the Voyager 1 tape recorder is still working. It just needs a little maintenance at 15 billion miles (24 billion kilometers). Good old tech! :grinning:

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Just think if NASA had bought the recorder from the Best Buy electronics stores here in the States, Best Buy could send one of their Geek Squad repair guys to fix it. Oh wait! 15 billion miles. Maybe not. Best Buy would probably charge an extra fee for that service call. :smile:

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The cost of a suicide mission… A 2 \times 47 = 94 years round trip :smiling_face_with_tear:.
Well, bad computation, in fact it is rather the time to go there as the Voyager will continue to go farther as you approach… The guy would be dead before arriving… And Voyager too…

Well, of course you would have to travel far faster than Voyager, else you will never catch it up…