Sensirion sht7x labview

[GHernandez]

Is there any repository for labview code for a sensiron sht71 sensor? Hooked up via daq
Any help would be greatly appreciated.

Message Edited by GHernandez on 04-11-2006 04:43 PM

[McKala[DE]]

I don't know of any code for that particular sensor.  You'll have to create your own code but depending on your DAQ board there are quite a few ways to go about developing it.  What DAQ board are you using?

Regards,

[unclebump]

Try this link.

http://www2.hmc.edu/www_common/EnvironCenter/research/SBeaini_AUB.pdf

[GHernandez]

    I am using a 6033 E card hooked up to a SCB-100 connector box. I have some lv code already, but i keep getting bogus data.

[McKala[DE]]

Did you write the code yourself or did you get it from a third-party?  Can you explain what kind of bogus data you are getting?  Are you seeing incorrect data or are you not reading a signal at all?  You can verify that your 6033E is functioning properly using the DAQ Diagnostic Utility, make sure that you disconnect the SCB-100 connector box before running the utility and that you have NI-DAQmx 7.5 or later installed on your machine.

You should also verify that you can read a know voltage or current using your LabVIEW program. 

Regards,

[GHernandez]

I am fairly certain the 6033E is working because we received from NI (new) about 2 months ago and hasn't been used. The code was written on site, not 3-rd party. But that is why I was interested at looking at someone who already wrote some code, although it might be diferent so I can get an idea if its correct code or not. I am currently bit banging it, which I believe is the best method to do so.

[unclebump]

I don't think you can wire this device to an analog input. It has four pins. VDD, GND, DATA, SCK

1. 2.2.1 Serial clock input (SCK)

The SCK is used to synchronize the communication between a microcontroller and the SHTxx. Since the interface consists of fully static logic there is no minimum SCK frequency.

2.2.2 Serial data (DATA)

The DATA tristate pin is used to transfer data in and out of the device. DATA

changes after the falling edge and is valid on the rising edge of the serial clock SCK. During transmission the DATA line must remain stable while SCK is high. To avoid signal contention the microcontroller should only drive DATA low. An external pull-up resistor (e.g. 10 kΩ ) is required to pull the signal high. (See Figure 2) Pull-up resistors are often included in I/O circuits of microcontrollers.

See Table 5 for detailed IO characteristics.

[GHernandez]

Yeah you are right, you cannot use the AIO. I am using the DIO channels.

[Henrik_Volkers]

here http://forums.ni.com/ni/board/message?board.id=170&message.id=137823#M137823

wha@atmel post a llb for the printerport that talks to an AD??? device, maybe that code gives you an idea...

[MarioLutz]

I wrote some LabView 8 code to communicate with the SHT15 with an NI USB-6008 DAQ device. I use the digital I/O lines. One line as SCK, two lines for DATA (one for writing, one for reading, both connected to the DATA line of SHTxx)
I used the sample code for microcontroller written in C (found on the website of Sensirion) to write the LabView driver. In the llb-file there is a main.vi and main2.vi as a sample program. You must change in the DAQ_Initialize.vi each "line"  for  your card.
You need DAQmx from NI for your DAQ-card and 3 free digital I/O lines.

bye