We used Fortran, although asm could be used and apparently there was a Pascal, but I never saw it. We actually did the dev cycle on a front end system (VAX/VMS or Unix) and submitted the program as a batch job (COS was a batch OS, the multiuser UniCOS didn't show up till much later).
I must have been an incredible opportunity working with a supercomputer. Did you ever compute a mathematical constant or an algorithm to a large precision out of curiosity?
Yeah...I got lucky. My third year or so at Georgia Tech a professor offered a "special topics" (e.g. not in the course catalog; his personal research interest) undergrad class in supercomputing. GaTech was good for little bonuses like this (I took Micheal Barnsley's first IFS class, too).
In addition to Crays, we got time on a CDC Cyber 180/990 and a 205, an ETA machine, and had cursory intro to NEC SX, BBN Butterfly, Multiflow Trace and a few other weird things noone has ever heard of. We wrote a handful of numerical methods programs for each (so, yes, computing mathematical constants and such, but more vector/array manipulations), and looked at how the architecture of the machines (short v. long vectors, register based v. memory based, vector v. MIMD v. VLIW) effected the speed of the programs and what optimizations/refactorings resulted in large speedups.
