NI6534 generating timed pulses with ACK line

[ray1234]

hi,

I'm programming in VC++ and I want to use the ACK line as an extra general purpose output line and generate a short timed pulse of length about 100ns,

I noticed I can't group control lines like regular data lines and use pattern I/O... what is the best way to do this? thanks

[Salvador_Santolucito]

Hi Ray,

I'm not sure if using the ACK line is what you want to do. When you set your card to do handshaking transfers, the ACK and REQ lines are used to perform the handshaking. If you want to use the ACK line to simply output a pulse, you would need to set up a dummy handshaking transfer on one of the digital ports and set it upt so that the ack line behaves how you like.

However, if you are going to use a digital port so you can configure the ACK line to operate this way, then you might as well just go ahead and use that digital port to do pattern IO. Then with the pattern IO, make your digital pulse on one of the lines. This would be much easier than using a handshaking port and configuring the ACK line. Either way you need to use a port.

-Sal

[ray1234]

hi Sal,

Can I use the PCLK line?

I tried to run a burst handshaking mode test with the following configuration:

status = DIG_Grp_Config(iDevice,1,1,0,1);
status = DIG_Grp_Mode(iDevice,1,3,0,1,1,7);

and I tried to probe the PCLK1 pin but there was no square wave coming out,

Isn't it suppose to generate a clock signal on PCLK1 if you configure burst handshaking mode on group1?

[Salvador_Santolucito]

Hi Ray,

What type of operation are you trying to perform when you set DIG_Grp_Mode(iDevice,1,3,0,1,1,7)?

For input operations, PCLK is used as an output clock pin. For output operations, PCLK is input pin. Perhaps your digital group is configured to do an optuput operation, in which case you will not be generating a signal on your PCLK pin. To generate on your PCLK pin, you need your group to be an input operation.

This is mentioned in the user manual in table C-3.

http://www.ni.com/pdf/manuals/371464d.pdf

-Sal