LabVIEW and "USB to 1-wire" (DS2490)

[MortenSvarre]

I have made an "USB to 1-wire adapter" using DS2490. I can communicate with the DS2490 using USB standard requests, but I'm having a hard time getting data from the device attached to the DS2490 (i.e. DS1820). I'm using LabVIEW 7express.

[TN]

Did you check your hardware driver? Try do download the current driver for your hardware.

[MortenSvarre]

My driver is OK. The only problem I have, is to perform non USB standard requests, such as 1-wire device data I/O.

[tomsch1]

i am interested in reading several ds1821 in a similar fashion if possible could you provide the vi that does the 1-wire communication

[TN]

Hello Tomsch1,

I am sorry we don't have provide example VIs. Please look the example VIs from LV. I am sure you can find some examples.
TN

[james_t_dk_home]

Hi morten.

Can you read the ID of the DS1820?
Have you had any luck with your code?

[KileenC]

Hi,

I did a little searching around on the Dallas Semiconductor website, and from App Note 177, it looks like the driver has a TMEX and OWCOM API. You can probably implement code to communicate to your hardware and then access that code via Call Library Function nodes or .NET calls in LabVIEW.

Also, I'm not sure how different the 2-wire communication protocol is to the 1-wire, but DS has App Node 215 with example VIs to show how communication to a 2-wire device can be done. If you have the control commands for the device, you can also just write your own VISA commands (as that App Note 215 demonstrates) to communicate to your device. There are also a couple VISA examples that ship with LabVIEW for you to take a look at.

Hopefully some of this will be helpful. Good luck.

Kileen

[james_t_dk_home]

HI KileenC

1-wire and 2-wire are a little different.
I to am having problems reading 1-wire devices and I'm using the OWAPI.
I do get a read of the device Uniq ID but I can not get a read of the temperature of the device.

Also se my post: http://forums.ni.com/ni/board/message?board.id=170&message.id=98107
If you want to try 1-wire for your self (and hopefully help the rest of us) my post tells you how to get free samples..... 😉

J;-)

[MortenSvarre]

Success at last.

I can now read the temperature from a DS18S20 via a DS2490 (USB-1wire), also available as DS9490.

I got a piece of code from Brian Tyler (dotnet.zip) and it worked with just a few adjustments to the .NET nodes.

Follow White Paper 6 from Maxim http://www.maxim-ic.com/appnotes.cfm/appnote_number/1740

Find Brians reply at http://forumstage.ni.com/ni/board/message?board.id=170&message.id=120501

This should do the trick.

[Lycangeek]

For my reply, let me give another URL (http://forums.ni.com/ni/board/message?board.id=170&message.id=120501). I'm not sure exactly what forumstage is but the link to dotnet.zip fails there. If you go in through just the regular forums.ni.com, then the link works.