In DIO-32HS , can I cascade two groups for a block transfer ?

[Sree]

In my application(lab windows CVI), I have to use a group with 3 ports for pattern I/O generation. In DIO-32HS, one can configure a group with either 1,2 or 4 ports . I tried to use two groups where one group is configured to 2 ports and another group is configured to 1 port. The program runs Ok with no error, but the buffer has bad data. What is happening is that instead of the bits being added they are being appended, resulting in bad data. I can't use a group with 4 ports as I need one port for other operation. Can anyone help me?

[TylerS]

Sree,

I'm unclear on what you mean by the bits are being appended instead of added. When you say added, do you mean mathematically added? What exactly do you want to happen between the data from 2-port group and the 1-port group? Also, if you are planning on using the 4th port, i just wanted to point out (in case you didn't already know) that you will only be able to use that port for DIO operations, not any kind of control operation.

TylerS

[Sree]

hi,

Thanks for the reply. What I tried to do was to use two groups( as O/P) and configured 3 ports. What I meant by appended data is that if the original data bits are 10, 11 , 12...they are stored in output buffer as 100, 0, 101, 0, 102, 0, 103(this is just an example) so instead of doing 10+0(mathematically)... it is doing 10&0( like a string).
My aim in my application is pretty simple i.e., load the data(24 bits, using pattern generation) and send an ARM signal whenever the data is latched. Other thing I tried to do, is configure group 1 for 32 bits and use control lines of group 2 as the data line. But the problem is that I have no means to know when the data is exactly getting latched.

[TylerS]

Sree,

I was confused by the example. If you could, give me a similar example, but either in binary or hex. Let me know what bits you output and exactly how it shows up on your computer. Also, how exactly do you have your 3 ports configured to receive (or transmit) the bits? What I mean is, if you have ports 0,1, and 2 in that order, is the LSB going to port 2 or port 0?

TylerS

[Sree]

Hi,

I am sorry to have confused you, but there's bug in my code. I have to fix it before I move further. But thanks for your response.I'll get back to you, if I am not able to figure it out . thanks