Buffered Handshaking for 6025E using Dig Buf Handshake In (8255).vi

[lyn]

I'm using Dig Buf Handshake In(8255).vi to do my handshaking for 6025E board.

a. DAC is suppose to give a low in the IBF pin after receving a high in STB pin, however my IBF pin is always low. What may be the cause?
b. Understand that port C of PCI-6025E can be configured for mode 1 or 2 for handshaking(from user manual) how do i configure?
c. According to the user manual, there is Mode 1(strobed input) and mode 1 (strobed output), are they different configuration or the same configuration with 2 different function?

[markwysong]

Lyn,

Your 6025 DAC card does not support buffered digital I/O. Therefore, you can not use this VI with this card.

The Dig Buf Handshake In(8255).VI is meant to be used with high-speed digital cards, such as NI-653X series.

Mark

[lyn]

Is there any standard vi that i can use to perform simple handshake?

a. Understand that port C of 6025E can be configured for mode 1 or 2 for handshaking (from user manual) how do i configure?

b. According to the user manual, there is Mode 1(strobed input) and mode1(storbed ouput), are they different configuration or the same configuration with 2 different function?

thks

[markwysong]

Lyn,

I apologize for my last posting. I looked at the manual for the 6025E, but I guess I didn't look hard enough. You are CORRECT that the 6025E does have handshaking capabilities, does utilize the 8255 chipset, and the 8255 VI that you were using should work.

For question a, according to the manual, any port can actually do handshaking, but they specifically talk about port C. I would recommend going back to your Dig Bug Handshake In(8255).VI diagram, and you'll see the DIO config VI. Right click on it, and select "Help". You'll get an explanation of how this VI works, and it shows more of how it sets up the card for handshaking, and the importance of the order of the ports listed in the port list. I believe port C has to be the
last in the list, and it will be used for the handshaking.

For your question b, these modes are dependent on how the port is set up (for input, or for output). Take a look at the difference between the above VI and the Dig Buf Handshake Out(8255).vi. You'll see the direction is different (output). If the mode is set to 1 (which just means the port needs to be strobed to be updated), the direction determines whether it's a strobed input or a strobed output.

Hope that helps.

Mark

[lyn]

I've read thru the explanation of the VI that you have mentioned but I can't find the part to configure/set the handshaking mode to Mode 1(strobed input). Pls advise, thks so much & best regards.

[markwysong]

Lyn,

In reading the 6025 manual again, it looks like you don't really "set" anything to the mode we both are confused about.

I will admit, I'm not an expert on handshaking with MIO boards, but here's my thoughts.

In the Dig Buf Handshake In(8255).vi, I believe the "mode" is defined by two inputs; one is the input to the DIO config VI that defines the ports as input, and the other is the input to the DIO Start VI that defines WHERE the handshaking will occur. The default is internal, in which the board strobes itself. When set to the I/O connector, it has to wait for a strobe.

Therefore, I believe this is how the mode is set.

If the "I/O connector" input is changed to "internal", this would be mode 0--no hands
haking.

With the input as "I/O connector" and the ports defined as input or output, this would be mode 1--handshaking with strobed input or strobed output.

With the input as "I/O connector" and the ports defined as bi-directional, this would be mode 2--strobed I/O.

Hopefully that answers your question.

I realize that this doesn't help with your signal problem, but if we can understand how the board is being set up, we can get there.

Mark