Newsgroups: comp.sys.transputer
From: asskleong@ntuvax.ntu.ac.sg
Subject: Re: T805 basic timings required
Organization: Nanyang Technological University - Singapore
Date: 10 Oct 94 10:21:30 +0800
Message-ID: <1994Oct10.102130.1@ntuvax.ntu.ac.sg>

In article <1994Oct8.101708.1@ntuvax.ntu.ac.sg>, eh6911171@ntuvax.ntu.ac.sg writes:
> Hi there!
> 
> I am currently facing problems in determining the basic computations timings 
> on a T805-20 and T805-25 MHz transputers using 3L parallel C compiler.
> 
> The basic operationn timings that I want is :
> 1.   The addition of two floating point numbers without any assignment, for e.g.
>  A + B.
> 
> 2.   The subtraction of two floating point numbers without any assignmemnt, for
> e.g. A - B.
> 
> 3.   The multiplication of two fgloating point numbers without any assignment,
> for e.g. A * B.
> 
> 4.   The division of two floting point numbers without any assignment, for e.g.
> A / B.
> 
> Thank you in advance.
> 
> R. Arul
> 

	There are two ways to your problems.

	1.  Look up from the transputer reference manual or databook or
other related publications possibly by Inmos or Prentice-Hall.  Some of
them give the time for the object code.  You can break down the desired
operations into object codes, such as load operands into registers, etc.
and add up all the timing to obtain the time required by the operation
concerned.

	2.  Write a simple program to perform the desired operation for
a certain number of times and divide the total time used to obtain the
time for one operation.  The following extract of the Occam code may be
useful (and you may need to convert it into Parallel C for your purpose).

	SEQ i = 0 FOR 2000
	  SEQ
	    clock ? start.time

	    a := b + c
	    a := b + c
		 .
		 .
		 .
	    a := b + c
	    a := b + c

	    clock ? end.time
	    duration := duration + (end.time - start.time)

	(Initialisation and declaration for variables have been omitted
for simplicity.)


	Hope this helps.


Best wishes,
Soon Khing




