How many instructions per frame?

 To get an idea of the complexity of code executing during one frame of the game, we can calculate an estimate of how many instructions are executed for each frame. 

The main CPU is the Motorola 68000 running at a 10MHz clock. 10MHz means each clock cycle takes 100 ns or 0.1μs. The game runs at 60Hz or 60 frames per second so each frame takes 16.6667ms. So in each frame there are 166,667 cycles. 

The M68k is a CISC processor and its simplest instructions take 4 cycles, but there are instructions that take more. An upper bound to the number of instructions executed per frame is thus 166,667 / 4 = 41,666.75 or just about 42 thousand instructions per frame. The real number varies per frame depending on the mix of instructions that are executed on it, and it probably never reaches this value of 42k instructions per frame because you don't expect to execute only instructions of 4 cycles, but something in the order of tens of thousands of instructions per frame seems right. 

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