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Unread 06-12-2003, 21:37
ErichKeane ErichKeane is offline
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Re: Space Limit--What is expendable?

Quote:
Originally Posted by Rickertsen2
I have done the same. The reason i specified unsigned chars is bc they take more instructions to process. This translates into larger programs and slower execution times. If you arn't having problems with speed and or space i wouldn't worry about it. If you want to demonstrate this for yourself, write a program that does some signed and unsigned operations, and then look at the assembly code.
Technically yes, you are correct, the difference between signed and unsigned mathematics is a little more processor intensive. It does not take more space though in the memory banks at all afaik. I believe all it does is use an unsigned Char, and then subtract the 127/128 or whatever in implementaiton. The difference is so minimal between the two, i never saw it as a problem.

I did a few things that helped me save a huge amount of space.
1- I reverted to completely integer mathematics, as opposed to floating point mathematics, which are horrid!
2- got rid of all unnecessary portions of the default code. That removed a large amount of the space (about 12% of our programming memory!), and left a good amount of the programming to me instead of some default setup.
3- Got rid of that printf library. It is easily the worst written print library i have seen in ages. Instead, my team is using the printword and printbyte and etc library in the utilities.

You guys have been a great help, keep the good posts comming.