This:
pos=(pos+7) Mod 256
Is a pretty trivial calculation for the processor.
Algorithms to generate random numbers tend to be much more complex, e.g. to simulate RANDOM numbers.
If you are really that bothered, you could pre-generate 1 million random numbers, stick them in an array, then pull values out of that array, starting at a random point each time. (At least, that *feels* like it would be quicker, albeit not truly random).
pos=(pos+7) Mod 256
Is a pretty trivial calculation for the processor.
Algorithms to generate random numbers tend to be much more complex, e.g. to simulate RANDOM numbers.
If you are really that bothered, you could pre-generate 1 million random numbers, stick them in an array, then pull values out of that array, starting at a random point each time. (At least, that *feels* like it would be quicker, albeit not truly random).