On the NI-7344, When using the Break Point Outputs as general i/o, how do you set the polarity

[falexander]

Hello

When using the NI-7344 and CVI.

I want to use the Trigger Inputs and Breakpoint Outputs as general I/O.

So I used the command

flex_set_hs_cap_pol  command to set the polarity of the Inputs 1-4 

How do you set the polarity of the Break Point Outputs as general i/o?

Thanks, 
Pat

[Logan_H.]

Hey Pat,

So, the breakpoint outputs can be set by using the function:

status = flex_set_bp_momo (boardID, axisOrEncoder, u8 mustOn, u8 mustOff)

More on this function and the MOMO settings can be found in this KnowledgeBase.

Logan H

[falexander]

Logan,

I have a MID-7654 four axis servo motor drive. This drive has a Trigger input and breakpoint output terminal blocks on the back. These inputs and outputs are NOT part of any axis or encoder.  I need to use these inputs and outputs as general purpose I/O (not as a high speed capture) . I use a PCI-7344 motion controller and use CVI to program. I use the functions in flexmotn.h to configure the drive.

On the older drives/boards, i used functions in the pcmotion.h to configure the old drives/boards. I used set_io_pol and read_io_port to set the polarity, direction, and read the input/output. 

As the new drive/board won't support Valuemotion, i have to use the NI-motion to congure the drive. The "ValueMotion to NI-Motion Conversion" help file says to use these nearest NI-motion functions:

set_io_pol --> flex_configure_hs_capture

read_io_port -->flex_read_hs_cap_status_rtn

where:

flex_read_hs_cap_status_rtn(u8 boardID, u8 axisOrEncoder, u16* highSpeedCaptureStatus);

flex_configure_hs_capture(u8 boardID, u8 axisOrEncoder, u16 captureMode, u16 operation);

The problem is both of these functions are asking for a "axisOrEncoder" as a parameter. What do i put in for this parameter as the trigger inputs and breakpoint outputs are not part of any axis or encoders. 

Are there any other functions i can use to set the polarity and read the trigger inputs? 

I have the same problem with: status = flex_set_bp_momo (boardID, axisOrEncoder, u8 mustOn, u8 mustOff)

what do i use for the axisOrEncoder to configure the breakpoint on the MID-7654?

Thank you,

[Joe D.]

Hi Pat,

Try using the Axis Control to set the breakpoints. The constant for that is NIMC_AXIS_CTRL. I was just wondering why you are not just using the digital I/O on Port 4 of your card?

[adithya]

HI

I am also looking for a solution to the same problem. I am using PCI 7334 card and it is connected to UMI 7764. As i dont have the digital cable of the card. I have decided to use breakpoint and trigger as digital output and input to control A.W on and off and resolution control of the driver. I am totally conufsed by the MOMO function etc. If you could help me by giving a valuable feedback it will be very helpful..

thankyou

[Paul_M.]

Hi adithya,

Check out this example to see how to use the MOMO functionality to control general purpose digital I/O with your 7334.

Paul M

[adithya]

I have already seen it ....

have many questions about that vi.

1. There should be 8 switches instead of 6. The Vi has oonly 6.

2. http://digital.ni.com/public.nsf/allkb/1C81EBA21D349D13C1256EDF0051521C check this link it gives you the binary to be used in must on and off to activate breakpoint 1. But in the vi you have refered to me they have used one input tat goes into must on and the same input goes to must off through a not gate. which makes it impossible to give binary on must on and off as mentioned in the link.

3. Does activating the breakpoint means it gives output in high state rather than low state. Or does that even matter.

will the breakpoint be active just by running that example vi? if so after its active how do i program with it in labview to send singals to the driver for performing the function am aiming at which is switching resolution.

have been spending weeks on this one issue and have the same problem with trigger too i know i have to use high speed capture vi...but i do not fully understand how it is converted to a digital i/o port and how to manipulate teh input or output of the digital port obtained from breakpoint and trigger.

i could really use your help

i thankyou for your previous response and i appreciate your help.

jithu

[Paul_M.]

Hi adithya,

Sorry for not being more clear in my original post. That example that I sent you will actually allow you to set the digital breakpoint values just by running the program.

The reason that there are only 6 boolean controls in that example is because bit 1 and bit 7 are actually set to 0 permanently. That being said, you'll have access to the 6 boolean values that you see in the example program. The first 4 boolean values will correspond to the 4 breakpoint terminals that you have on the UMI respectively. Therefore if you run this program and set the first boolean control to true, it will drive the BP1 terminal high on your UMI.

From my tests here it doesn't seem that you'll be able to use the boolean controls for 5 and 6 as they don't correspond to an actual breakpoint terminal.

So in summary, this example will drive those breakpoint terminals high if you set the corresponding boolean control, 1 through 4, to true.

Paul M

[adithya]

That was very clear thankyou. I did test the VI to activate breakpoint one exactly as you have mentioned. But itdid not give me any response. Now am guessing may be breakpoint one of UMI itself is not working. I will rewire the driver to breakpoint 2 or 3 or 4 and see if it works. Will update you with the results.

thankyou once again