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DDS scaling

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DDS scaling

Postby Hivemind1 » Wed Oct 15, 2014 3:05 pm

Hi

I decided to see about adding in autosense resistors to make some in house built sensors work plug and play however I have run into a few problems.

I have added in the 1% tolerance sensor into a simple light sensor using an LDR and created a DDS file in the correct pico folder to see if it would sense it and change the name to correct which worked lovely.

I then proceeded to type the raw and scaled data in and when I started using it to try and sense the light level in Lux I received readings that were incorrect and didn't match the scaled version of its raw data (I checked the ambient light which was approximately 0.5V which scaled too about 800 Lux in my file I instead received either 0 or 0.5), the scaling file below is below. after this didn't work I tried changing a few settings such as the method, out of range and noofpoints just in case but this only resulted in picolog no longer picking the scaling file up and now it only reads as a standard V sensor.

any help would be greatly appreciated
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scaling.txt
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Re: DDS scaling

Postby Hivemind1 » Fri Oct 17, 2014 7:47 am

Just an update it now auto detects, would appear the Picolog software was crashing and not picking up the new scaling file. however the scaling itself still fails to correctly show as my number rises when it should fall and is nowhere near the correct values.
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Re: DDS scaling

Postby Hitesh » Mon Oct 27, 2014 3:15 pm

Hi,

If you use the same values in a lookup table in the Scaling dialog for Input channels, are the readings scaled correctly?

Regards,
Hitesh

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Re: DDS scaling

Postby Hivemind1 » Fri Nov 07, 2014 9:16 am

Hi

Apologies for the late reply we have been on holiday, we will give it a go hopefully at the beginning of next week and report back to you.

Thanks
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Re: DDS scaling

Postby Glovisol » Tue Nov 25, 2014 4:03 pm

Hitesh wrote:If you use the same values in a lookup table in the Scaling dialog for Input channels, are the readings scaled correctly?


To make sure a new .DDS file is picked up, it is advisable to start Picolog afresh, as soon as the new file is placed in the folder. However after many tests it seems to me that, for some unknown reason, scaling in .DDS is erratic. It works most of the time,but there are istances where it does not work, no matter how long you try. This matter should be looked into by an expert.
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