Handshaking parameters in pci 6534

[Vishal]

I have faced a problem while using the example pattern -burst -1board - continuous available on net.Here we can do input 7 output operation simultaneously.I have selected port 0 for output & port 2 for input. Now i am performing the burst mode for this. I have connected req1-req2,ack1-ack2,pclk1-pclk2. If i am performing the test with ack & req polarity active high, it works properly but if i am keeping it active low it is not working. Why it is like this?
In the same example we can do the pattern io also. For that we have given the clock right. Now for handshaking parameter and for burst mode pclk frequency is determned by ack modify amount right? So when we are doing burst operation, what is the work of clock frequency specified at
DIO start?
2. ) Please explain me the double buffered mode briefly.
3. ) Can i use pattern mismatch fro start trigger?
4. ) When we read a port with port lines open it will read all 0's right? Will the DPULL affect it? i mean to say that if DPULL is connected to VCC will it read all 1's?

[Sarah Thompson]

Vishal,
I think alot of the theory behind the questions you are asking can be found in the 653X User Manual: http://www.ni.com/pdf/manuals/321464c. pdf. Specfically Chapter 3 on Handshaking. Feel free to post again if something in the manual isn't clear.

I also suggest looking through the application notes for Digital Input/Output. http://zone.ni.com/devzone/devzone.nsf/ webcategories/ DE8672528D9A733C86256797004C659A?opendoc ument&node=DZ52278_US

Here are a few other pages that may help in the manual:
3.) page 2-20/21
4.) page C-5 and D-5