Picoscope 4227 and Voltage position

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daniele bartalesi

Picoscope 4227 and Voltage position

Post by daniele bartalesi » Wed May 11, 2011 8:14 am

Good morning.
It is possible to set the voltage position of the channel?
I haven't found any function to do this. Can you help me?

Chris
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Re: Picoscope 4227 and Voltage position

Post by Chris » Fri May 13, 2011 8:59 am

Do you mean the voltage range?

have a look in the programmers guide at the ps4000SetChannel function

This is where you specify the voltage range you are using.



http://www.picotech.com/document/pdf/ps4000pg-en-5.pdf


Then to get the mv value back from the adc value returned from the scope, use the equation.....


mV = (ACD count x mV range) / max value (note: max value = 32764)

so on the +/- 5V range, an adc count of 12950 would give a 1976 mv value
(12950 x 5000) / 32764

daniele bartalesi

Re: Picoscope 4227 and Voltage position

Post by daniele bartalesi » Thu May 19, 2011 9:38 am

Do you mean the voltage range?

No i speak to the voltage offset of the channel

In our software (picoscope 6) it's possible to configure offset by the advanced options for the channel a/b

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Re: Picoscope 4227 and Voltage position

Post by Chris » Thu May 19, 2011 10:05 am

So you will just need to add whatever offset voltage you want onto the mV value you calculate from the returned adc count, and the channel range.

daniele bartalesi

Re: Picoscope 4227 and Voltage position

Post by daniele bartalesi » Thu May 19, 2011 11:47 am

Yes,
I want insert into a channel of the picoscope a signal (for example: 3Vpp sinusoidal) and add at this signal a offset value, (for example: -3Vp).
The signal result is the main signal shifted of the offset value. (in the example the signal result oscillates from 0 to -6volts)
thank you
Daniele

Chris
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Re: Picoscope 4227 and Voltage position

Post by Chris » Thu May 19, 2011 2:42 pm

There is no API function to do this. You will just need write your code to add the offset, or calculate a percentage offset for the ADC count values you get back from the scope.

daniele bartalesi

Re: Picoscope 4227 and Voltage position

Post by daniele bartalesi » Thu May 19, 2011 3:35 pm

ok but can you explain me how realized the offset function?

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Re: Picoscope 4227 and Voltage position

Post by ziko » Fri May 27, 2011 1:01 pm

Hi Daniele,

You would have to write this yourself, you can either add an offset to the ADC counts or do it as a percentage of the ADC counts.

Kind regards
Ziko

Technical Specialist

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