28 Jul
2008
28 Jul
'08
2:12 p.m.
I am trying (and failing) to learn how AMOS Basic (and
Amiga's) store
floating point numbers. Whilst it is clear that it uses Motorola Fast
Floating Point (MFPP) I have been unable to get it to work based on an
equation found online (the Amiga RKRM's all say to use the FPP
functions in the maths libraries, and also confirm the layout - 24 bit
mantissa, 1bit sign, 7bit exponent). Am I doing something wrong with
my maths??
IF it is the same as IEEE single precision,
there is a sign bit,
and 23 bits to store a 24 bit mantissa, (normalization always forces the
highest bit on, so there is no need to store it),
and an 8 bit exponent (with 128 offset)
Zero, therefore, has to be stored as a special case.