Has anyone any idea where I can get a double precision maths library which will work with the Keil C51 compiler.
Get a math text book. Four function float will not be that hard add the mantisas adjust the exponents. A better Idea is to take the final formula and hard code it multiplications first then divides. Then again it would be easiyer to code 64 bit (or longer) ints than floats
Thanks for your thoughts Neil I have written 32-bit maths routines in assembler (on 6809 processors admittedly & integer only), so this looks less daunting the more I think about it. As you say it is just integer maths on the mantissas but with a watchful eye on the exponent. I plan to write it in C since I am not familiar with 8051 assembler. best regards - Paul