The TPHOT code has been implemented on the Cray YMP with eight CPUs by researchers at Lawrence Livermore National Laboratory and yields correct results on our test problems. This code was macrotasked on the Cray YMP, taking advantage of its shared memory. The code yields identical results for a given number of tasks, regardless of the number of Cray CPUs which are actually executing the simulation, including a single processor which executes all tasks in sequence.