Sensirion EKP-3 Code to read the raw ticks from the SDP6xx Pressure Transducer with LabVIEW

[davekorpi]

Guys:

I have seen the post here about the Temp Humidity sensor: Ref: http://forums.ni.com/t5/forums/replypage/board-id/170/message-id/749141

Pardon the post under a new topic but I was advised to post it in a "new thread"... With the Device name in the title..  If this is a no-no let me know...

Here is a question for the EKP-3 using the USB for the SDP6xx Here is an overview of what I am looking for... 

http://www.screencast.com/t/RUDOisSvqC

I have the Sensirion EK-P3 Stick to talk to the pressure transducer..

This stick is made by these guys: http://www.codemercs.com/349/

My question is how did you figure out the binary code to read the T and RH from the  iowkit.dll

I want to read the RAW TICKS from the device that represent pressure. They go from 0 - 65535 and I have spied on it with WireShark and can not wrangle the binary code to read the raw ticks I am after.

I made a video you can look at to see what I want from my learnings from this post: 

http://www.screencast.com/t/UnCTJtvWLe

I attached the DLL as well (Just rename it to iowkit.dll because LabVIEW does nol like dll's in attachments... so you do not have to mess with the msi.

You may contact me directly at dave.korpi@gmail.com

Thanks!

Dave Korpi

Ref: http://forums.ni.com/t5/forums/replypage/board-id/170/message-id/749141

[cade]

Hello Dave,

For some reason I cannot open that other forum post you were referencing, can you please try to re-include it? 

Also, maybe I missed this, but can you inform me of what you mean by raw ticks?

Thanks!

[davekorpi]

Cameron:

Thanks for the reply! Impressed, AS ALWAYS, by the customer service NI ALWAYS gives! Unbelievable, yet I have grown to LOVE it and I so try to emulate what yall taught me when I provide service to follks I work with!

Here is the reference link:

http://forums.ni.com/t5/LabVIEW/Sensirion-SHT15/m-p/1589710

Raw Ticks refer to the actual raw signal given by the Sensirion. It uses a 0 - 65535  (16 bit) output for +/- 0-5 InH2O (Or whatever the range is) So 32,767 is nominally 0 (ZERO) and 0 is nominally - 5 inH2O and 65,535 is nominally 5 inH2O.

The other signals they output are SCALED and do not provide the RAW OUTPUT I desire to use.

[davekorpi]

A little more info to further clarify.. A video... http://www.screencast.com/t/0VmlqJ2nP

You can see from here http://www.screencast.com/t/0VmlqJ2nP (same as right above)  I want to know how to invoke proper communication (like I show with the Sensirion USB RS485 Sensor Viewer software)  with the SDP 6xx series and then how to select Raw Ticks and then how to read the Raw Ticks. Read ONE TICK is desired and I do not need to STREAM ticks...

[davekorpi]

Cameron... Wondering if you knnow how to get a 2's compliment for a 12 bit value in LabVIEW?

I am looking to get the code to communicate to this top secret Sensirion product.

Anyone know if I am properly sending the commands at 1, 2 and 3 of the image below?

At issue, I think, is getting the two's compliment of the two 8 bit registers at Data LSB and Data MSB using LabVIEW...

I have been working with the wizards at http://www.codemercs.com/258/?L=1 who have been EXTREMELY helpful.

They have an AWESOME I2C to USB converter that you can get OEM devices to work for your I2C project. It is a single channel version of the NI-8451

Anyone out there can figure this out so I can read the RAW TICKS from the Sensirion SDP6xx product line?

Thanks a million! 

Feel free to contact me at 831-455-0418 (pacific time) or dave.korpi@gmail.com

[davekorpi]

Forgot to insert image...

[davekorpi]

Here is a two's compliment for a 12 bit integer created by Xu from his post:

Cameron.. See how to do with this..

Do you want 1,2,3,4,5,6,7,8,J,K,L,M or J,K,L,M,N,O,P,Q,1,2,3,4? Or something else?

Then take 2's complement?

[davekorpi]

Complete LLB with two's compliment implementation but I do not think I did it right...

Any hints to help?

Anyone on the planet have any success talking to the Sensirion SDP6XX series in LabVIEW?

What up with the 12 bits? That's 0-4096 but I KNOW the device goes from 0-65,535 with the "zero" at 32,767 and full scale at 65,535

At this point I can not tell you how utterly dissapointed I am with the company called Sensirion. So.. as much as I LOVE the concept of the product I am fiercly looking for ANY OTHER COMPANY on the planet who has made anything similar because I would drop them like a hot rock given their total lack of customer support.

Anyone know someone at Sensirion who is willing to help, Know who the president, or director is so I can invite them to provide simple instructions on how to use their product with the most popular programming language, LabVIEW, on the planet?

[davekorpi]

I am still working with this silly thing! Can anyone figure out how this thing works> The datasheets and sample code are not clear.

All I am looking for are the few hex values to do the following:

1) Set up the measurement as shown in the 1 in the graphic.

2) Send the correct value to read the desired variable as shown in 2 in the graphic.

3) How to cipher the output.. I want the full 16 bits...

See this video....  

http://www.screencast.com/t/VWFYx7mc

See if you can figure out this crazy thing! I am sure I am missing something VERY SIMPLE! 

In the end I really only need to know the right values to put in the graphic below...

What am I missing??

[cade]

Hi,

I apologize for taking so long to respond to this forum, but I am a bit confused as to what you are looking for.  Do you want to ascertain the two's complement of a 12 bit or 16 bit number on the output?  Doing this with a 16 bit unsigned interger should be fairly staight forward.  Does this VI help at all?