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.DDS files and the DrDAQ

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.DDS files and the DrDAQ

Postby Glovisol » Sun Nov 02, 2014 8:46 am

I have just received a brand new USB DrDAQ and I have been unsuccessfully trying to make it work reliably on EXT. INPUTS 1 - 2 & 3 with scaling .DDS files.

1 EQUIPMENT IS AS FOLLOWS.
PC: IBM ThinkPad XS61
OP. SYSTEM:Windows 7 Professional.

2. EXT. SENSOR
LM 35 Temperature sensor fed by the DRDAQ 5 V output of each EXT. INPUT.
Autodetect resistor between pins 2-3, EXT. INPUT: 3.3 kOhm.

With local temperature of 20.5 °C each input (without scaling) reads correctly 205 mV. Standard Pico temperature probe connected to EXT. INPUT 3 reads 20.5°C and internal scaling file for standard probe works correctly.

3. MY SCALING FILE: Experimental.dds

[Scale1]
Resistor=3.3
LongName=Temp.LM35
Units=°C
MinValue=10
MaxValue=100
OutOfRange=0
Places=1
Method=0
NoOfPoints=3
Raw1=0.1
Scaled1=10
Raw2=0.5
Scaled2=50
Raw3=1
Scaled3=100

The scaling file was written on Word Pad as a .txt file, then copied into C:\Program Files\Pico Technology\Pico Full and then changed from Experimental.txt into Experimental.dds.

I then connected the LM35 3 wires to EXT. INPUT 1 with a 10 KOhm ballast resistor between Pins 1-2, the autodetect resistor of 3.3 kOhm between pins 2-3 and the supply input of the LM35 to Pin 4.

With the DrDAQ connected via the USB port, I opened Picolog, went thru the standard steps, activated EXT.INPUT 1, went to "OPTIONS" and selected "scaling by file". The system does not see .DDS files directly, unless you click on "all files". The Experimental.DDS appeared in the PicoLog window, but sometimes it had no effect whatsoever; sometimes it just did the correct scaling, but did not change the titles and units. Just once I had the proper performance, but, when I tried to reproduce it a second time, it failed.

Subsequent tries on the other EXT.INPUTS gave similar results.

I tried to re-start the PC; to disconnect and re-connect the DrDAQ. I removed PicoLog along with the entire directory; I re-installed PicoLog again (always used Ver. R5.23) but the action of the .DDS file on the PicoLog/USB DrdAQ combination remains impredictable and unreliable.

The last straw is that sometimes EXT. INPUT 1 appears TWICE on the channel list on PicoLog and sometimes some of the titles and scaling of the Experimental.DDS file appears EVEN IF I HAD THE FILE REMOVED FROM THE Pico Full directory!!

It looks like a mess to me: any suggestions? Where did I go wrong?
Glovisol
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Further on .DDS files & USB DrDAQ

Postby Glovisol » Sun Nov 02, 2014 10:54 am

Concerning my previous post on difficulties with .DDS files, I suspected that some other software installed in the PC might prejudice the connection between the .DDS file and the DrDAQ. I therefore took another IBM X61 (W7 O.S.) with a bare minimum of software installed, and prepared the same .DDS file.

This time the file drives EXT. INPUT 1 automatically as soon as I open Picolog: there is no need to go to "parameter scaling". So this part is working fine. Now the problem is the scaling, that does not work: I only get a reading identical as the physical input: e.g. 0,21 instead of 21, as should be expected. I hope to solve this problem as well..

In any case my experience shows that there must be some interactions among PicoLog and some software already installed in the previously used PC.
Glovisol
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Posts: 114
Joined: Sat May 11, 2013 10:03 am
Location: San Marzano Oliveto, Asti, Italy

.DDS files and the DrDAQ - More experience

Postby Glovisol » Sun Nov 02, 2014 8:38 pm

As per my previous update, the .DDS file was now able to control all parameters of the DrDAQ, but the scaling was NOT operating: e.g. reading shown was without scaling. After many tries the .DDS file became bad and with the file in the Pico Full directory the DrDAQ would not start. This I solved by deleting the file and making a new one. But still no go with the scaling....

After a while I started suspecting something wrong with the software again, even if I was using the second, cleaned out IBM X61 as previously described. I removed the PicoLog program, deleted the directory and re-installed a fresh copy (R 5.23). To my surprise and joy the DrDAQ started working perfectly!!

Conclusion: This .DDS file business works all right, but the PC and the software must be spotless, otherwise you will have a lto of trouble!
Glovisol
Advanced User
Advanced User
 
Posts: 114
Joined: Sat May 11, 2013 10:03 am
Location: San Marzano Oliveto, Asti, Italy

.DDS files and the DrDAQ - More experience

Postby Glovisol » Mon Nov 03, 2014 6:18 am

As per my previous update, the .DDS file was now able to control all parameters of the DrDAQ, but the scaling was NOT operating: e.g. reading shown was without scaling. After many tries the .DDS file became bad and with the file in the Pico Full directory the DrDAQ would not start. This I solved by deleting the file and making a new one. But still no go with the scaling....

After a while I started suspecting something wrong with the software again, even if I was using the second, cleaned out IBM X61, as previously described. I removed the PicoLog program, deleted the directory and re-installed a fresh copy (R 5.23). To my surprise and joy the DrDAQ started working perfectly!!

Conclusion: This .DDS file business works all right, but the PC and the software must be spotless, otherwise you will have a lot of trouble!
Glovisol
Advanced User
Advanced User
 
Posts: 114
Joined: Sat May 11, 2013 10:03 am
Location: San Marzano Oliveto, Asti, Italy


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