From: mahsad on
hi,again
first i use TMS320C54x and i'd like to immplement fixed point programming
on C or assembly(that doesn't mather).how can i do this?
How can i convert my program(Goertzal algorithm) to a fixed point
program?
(first i'd like to convert it in c)
can anyone help me again?
From: Muzaffer Kal on
On Sat, 05 Sep 2009 05:39:01 -0500, "mahsad" <mahdi_kbm(a)yahoo.com>
wrote:

>hi,again
>first i use TMS320C54x and i'd like to immplement fixed point programming
>on C or assembly(that doesn't mather).how can i do this?
>How can i convert my program(Goertzal algorithm) to a fixed point
>program?

At a high level the flow is very easy: You run all your expected data
through your current implementation and find for every
storage/calculation unit the dynamic range (minimum/maximum values all
the nodes in your graph can take). Then you quantize your input,
storage and calculation units so that you still meet your performance
criteria.
The first number gives you the whole portion of your fixed point
number for each unit and the second number gives you the fractional
portion. Then for every unit you assume an X.Y representation and
convert your calculations to conform to this format.
As always the details are left to the practitioner.
--
Muzaffer Kal

DSPIA INC.
ASIC/FPGA Design Services

http://www.dspia.com