PowerBasic rocks!



I just tried a test loop to add an array of 64 million 16-bit signed
integers into an array of 32-bit signed integers. This is to get an
idea of how long a signal averaging (summing, actually) thing might
take on a Pentium based SBC.

On my HP winXP desktop, writing a very dumb PowerBasic loop...

FOR Y = 1 TO 10

FOR X = 1 TO 64000000
S(X) = S(X) + A(X)
NEXT

NEXT

(where X, Y, and S() are longs)

this takes 2.25 seconds, or 0.225 seconds to do the 64M sum. That's
3.6 nanoseconds per loop iteration.

I could rewrite this using pointers and it might be faster.

We tried it on a Kontron MiniITX SBC, in C, with pointers, Linux but
with a wimpier processor, and got about the same run time.

We'll acquire 64M samples once a second or so, so the signal averaging
doesn't look like a showstopper. I was impressed.

There may be some MAC/array instructions buried in the x86
architecture that might be even faster.

John

.

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