AnsweredAssumed Answered

vrf SLOWPOKE

Question asked by VRFuser on Mar 20, 2002
<html>Hi John,

The peek/poke dll was never intended to provide anything other thanminimal capability to transmit a parallel data pattern. Specifically, itdoesn't use any technology normally used to optimize transfer rates foreither large or small data blocks -- like DMA, for instance. It'simplementation requires a transition from user mode into kernel land forevery data byte transferred. That transition is slow. A better choice forwhat you want to do would be a GPIO card, or maybe one of the other pcplug-in cards that support parallel digital IO. The following is a linkto a web page that details the software support for the various IOcards.

<font color="#0000FF"><u><a href="http://ftp.agilent.com/pub/mpusup/agilent/iolib/IOIntfMatrix.html" eudora="autourl">http://ftp.agilent.com/pub/mpusup/agilent/iolib/IOIntfMatrix.html

</a></u></font>HIH,

At 11:01 AM 3/21/02, john.quillinan@philips.com wrote:
<blockquote type=cite class=cite cite>Hello everyone,
I'm having trouble with the execution speed of peek poke  DLL thathave been referenced in the past
I'm using the parallel port to talk to my DUT to give it instructionsthen I test the DUT to see if the instructions are carried out.
The fastest I can get the bits to move is around 160K and I have anapplication where I need to move bits at >500K
I've tried streamlining my code but it seems that the programmingoverhead is slowing it down.  I've had success
doing this same thing in lower level languages.  I'm beginning towonder if Vee is digital friendly.


John Quillinan
Test Engineer
315-682-9105 x2568

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---------------------------------------------------------------------</blockquote><x-sigsep><p></x-sigsep>John Dumais
doomer@soco.agilent.com
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