topic Re: SPI Digital Waveform Library in Components

[Deprecated] SPI Digital Waveform Library

Christian_L — Tue, 04 Jul 2023 16:43:07 GMT

Please provide feedback, comments and questions on the SPI Digital Waveform reference library in this thread.

- David

(posted by Christian on behalf of David)

Edited to remove the link. This library is no longer available from NI

Re: SPI Digital Waveform Library

sugeo — Mon, 16 Mar 2009 08:22:18 GMT

Hello,

I'm using this library to generate the SPI waveforms. How do I output/input the signal waveforms (CS, MOSI, MISO, SCLK) using a PXI-6509 DIO? I've built individual channels with , each one to handle one signal. However, I could not output them simultaneously, so that all the timings configured using the library are kept. How was the intended method to do this?

Thanks,

Su Gin

Re: SPI Digital Waveform Library

sugeo — Mon, 16 Mar 2009 08:26:57 GMT

I forgot to add: With the VI shown in the image, I'm getting a varying amount of delay between the signals.

Thanks,

Su Gin

Re: SPI Digital Waveform Library

David S. — Mon, 16 Mar 2009 21:41:32 GMT

Hi sugeo -

You'll only be able to use the SDW waveform with a clocked digital I/O device. Software-timed I/O devices like the 6509 can't generate or acquire the data deterministically, nor can they toggle lines simultaneously. Devices that can clock their digital I/O include the M-Series DAQ (62xx) and 653x, 654x, and 655x High-Speed Digital I/O.

Re: SPI Digital Waveform Library

sugeo — Tue, 17 Mar 2009 08:44:24 GMT

Hello David,

Thanks for clearing that up. I would have to generate/acquire one bit from each line and move through all the lines sequentially until I have all my bits, right? Such as described by Tom in Message 16 of 25 in http://forums.ni.com/ni/board/message?board.id=70&thread.id=7192&page=2?

Would generating SPI waveforms on PXI-6723 be any different?I noticed it has some counter pins and digital routing ability.

Regards,

Su Gin

Re: SPI Digital Waveform Library

David S. — Tue, 17 Mar 2009 15:27:44 GMT

Hi Su Gin -

Tom's example approximates a SPI exchange using software-timed control of static DIO pins. The SDW was designed around the assumption that a device's DIO are controlled by a free-running clock, so its waveforms won't work with his programming model.

The 6723's DIO are also static, and so that device can't be used with the SDW. Looking through the NI Example Finder, I see that the examples Correlated Dig Write With Counter and Correlated Dig Read With Counter list support for the devices that can control their DO and DI pins (respectively) with a free-running clock. You may want to use that as a rubric for which DAQ devices can be used with the SDW.

(Note that the DAQmx-based HSDIO devices -- 653x -- aren't listed because their programming model is different.)

Re: SPI Digital Waveform Library

JeyZ — Wed, 01 Apr 2009 12:51:41 GMT

Hi,

Can you provide examples integrating these SPI waveforms with DaqMxRead/Write ? I am using 4 separate DIO lines of PCI 6229

connected to the Master Device(the device is generating the clock).I should both read and write data to that device through SPI

Re: SPI Digital Waveform Library

Priyatham — Fri, 24 Apr 2009 23:44:29 GMT

We have an ASIC out to fab and we're doing its evaluation planning and are in the phase where we are purchasing all the products needed to evaluate it. The digital portion of the ASIC can be communicated via an SPI, so we'd like to have a set-up where we can give inputs to the SPI along some other analog inputs and be able to read the digital outputs(on SPI again) and analog outputs. I know that Labview accompanied with compatible hardware will be able to do it, but not sure exactly as to what hardware we should resort to. I'm completely new to this Labview/accompanying hardware and any help would be hihgly appreciated. Thanks.

Priyatham.

回复： SPI Digital Waveform Library

中国view — Sat, 25 Apr 2009 11:16:27 GMT

hello,

can i use the SPI DIgital Waveform Library on PCI-6251? if can,How do I output/input simultaneously the signal waveforms (CS, MOSI, MISO, SCLK) with PCI-6251 digital I/O? IF can't, can i simulate the SPI Bus (to high-speed communication) with PCI-6251?

thanks

view

Re: SPI Digital Waveform Library

David S. — Mon, 27 Apr 2009 15:25:56 GMT

Hi Priyatham -

NI has an entire fleet of products capable of helping you with your ASIC test. Figuring out which ones are appropriate for your performance and cost tradeoffs usually requires that we understand a fair amount of the details in your system. I recommend contacting your local NI sales person or office for help selecting the right products in a confidential discussion.

Re: 回复： SPI Digital Waveform Library

David S. — Mon, 27 Apr 2009 15:41:11 GMT

Hi view -

I've been meaning to explain this formally. Give me a week, and I'll have a new document up that explains how to use this library with DAQmx and HSDIO hardware.

Re: 回复： SPI Digital Waveform Library

Savageaggie — Mon, 27 Apr 2009 15:41:56 GMT

Hey Priyatham,

National Instruments offers a number of products that can be used for first silicon validation, and characterization testing in PXI with LabVIEW, or other programming languages. We have more information at ni.com/semiconductor, including a reference architecture for common DC measurements on chips.

I'd be happy to help get you more information, and get you in touch with one of our local field engineers to help you out. You can reach me at scott.savage@ni.com.

Thanks,

Scott Savage

National Instruments

Market Development Manager - Semiconductor Test

Re: 回复： SPI Digital Waveform Library

David S. — Thu, 07 May 2009 18:28:18 GMT

Hi all -

I've published a new Reference Application that should prove useful when working with the IDW, JDW, and SDW libraries: Serial Protocol Communication with Digital Waveform Devices. It explains how to configure an NI-HSDIO or NI-DAQmx based device to work with one of these libraries. Check it out, and please rate it!

Re: SPI Digital Waveform Library

sugeo — Tue, 12 May 2009 17:17:44 GMT

Hi guys,

I'm still thinking of using the PXI-6723 for my SPI communication but with a HW clock. The 6723 has a 20MHz and 100kHz timebase used for the counters (a part of DAQ-STC). In the Analog Output Series User Manual (370735e.pdf) Page 1-2 it says "The DAQ-STC offers PFI lines to import external timing and trigger signals or to export internally generated clocks and triggers. The DAQ-STC also supports buffered operations, such as buffered waveform acquisition, buffered waveform generation, and buffered period measurement".

So I guess it would be possible to use the PFI0 and PFI1 pins as SCLK and DOUT for SPI writes, if the signal output of the pins are in sync. Is that the case?

Thanks,

Su Gin

Re: SPI Digital Waveform Library

David S. — Tue, 12 May 2009 21:33:10 GMT

Hi Su Gin -

That quote is discussing the capabilities of the Analog Input and Analog Output functions on the device. The DAQ-STC chipset does not support Correlated DIO. (The DAQ-STC II does, and M-series devices, 62xx, are based on this chipset.) You cannot use the 6723 for hardware-timed digital I/O operations.

Re: 回复： SPI Digital Waveform Library

Priyatham — Thu, 21 May 2009 00:32:12 GMT

Hi David

Im a newbie to the Labview and Im trying to use 6551 for SPI. So the reference application you posted there and the example were of a great help. Especially the example helped me speed up in the learning curve. Although I have noticed a small bug in the example and wanted to inform you of that. I think in the front panel of the SPI example, under the category SPI channels, the text of CS and SCLK are swapped. ie the input field adjacent to CS corresponds to SCLK and vice versa.

Thanks,

Priyatham.

Re: 回复： SPI Digital Waveform Library

David S. — Thu, 21 May 2009 14:47:20 GMT

Hi Priyatham -

Thanks for the feedback. The names assigned to signals in a digital waveform are actually stored in the graph object (as Plot Names), not in the waveform cluster. As such, they aren't necessarily updated properly when the waveform data changes. To do this, I would have had to add a lot of ancillary code to the example programs to manage the channel names in the graph object and update them based on how channels were assigned to the waveform cluster. I wanted to keep the examples simple and straightforward, so I chose not to do this. Of course, you can manage those names however you like in your own applications.

Re: 回复： SPI Digital Waveform Library

JeyZ — Thu, 21 May 2009 17:05:39 GMT

David,

I am using the M series 6229 card for emulating SPI.

We are using the concept of using counter and try to generate/acquire through SPI lines>it is working to some extent except problems like getting one extra bit at the start., sometimes not able to receive the valid data,or getting valid data after two three reads etc are happening . But basic operations like Master/Slave communication is fine.But no reliability.How can i make this software a reliable and a consistant one.I did not try using SPI library yet.I am directly writing/Reading bit array of the necessary data into DAQmx read/Write functions.

One more question,can i use the same card for I2C operation because as you mentioned tristating is required for the SDA line of the I2C protocol for getting the acknowledgement.Is this card having that capability?

Re: 回复： SPI Digital Waveform Library

David S. — Thu, 21 May 2009 19:01:55 GMT

Hi JeyZ -

In the past, I've worked with microprocessor-based slave devices that have nondeterministic response times to a given query from the master. For example, I would send a data query in the first byte, then expect to clock out the data from the slave in the next byte. If the slave device wasn't done with its search/retrieve routine, it had no data in the output register so all I clocked in was x"00". Could something like this be happening to you? Do you have a datasheet for the slave device you're communicating with that you can link publicly?

You may also try using the SDW library to build the waveform. It will guarantee that timing parameters for the bus are met and all edges in the waveform conform to protocol requirements. Alternatively, I can only ask that you post more information about your application software and the device you're communicating with, so we can help you debug it.

In response to your question about using the 6229 for I2C, that device does not have a per-cycle tristate feature. At present, only the 655x devices support that capability. Without it, you would have to do a lot of work to get this device communicating over I2C, and I can't guarantee it'll be possible in the end.

Re: SPI Digital Waveform Library

David S. — Fri, 22 May 2009 20:29:28 GMT

Hi all -

SDW v1.0.1 has been released. This version addresses a bug in the preallocation of a waveform with multiple CS lines, as well as some minor issues with consistent connector panes across polymorphic instances. You can get it on the SDW page.