How to make .cysch layout for voltage divider of analog input signal

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Anonymous
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I have a pressure transducer circuit that outputs a voltage between 0-5V.  There's a pin connected to that output that I connect to analog pin P2[2] on the PSoC 4 board.  I was wondering how to divide this down to meet the 3.3V max VDDA for the ADC SAR Sequencer.  Right now I have my "Transducer" analog input pin connected to the 1st pin of the 12 bit ADC (the 2nd going to ground).  For the divider, I have R1 as 5k and R2 as 10k, connected to the PWR Vdd (all of which is fed to external terminal of the analog pin).  Is this how it's supposed to be connected in the TopDesign.cysch?

   

I attached the project bundle.

   

-Anthony

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Bob_Marlowe
Level 10
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Not quite. Better connect the transducer output instead of Vdd to your resistor ladder.

   

 

   

Bob

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Anonymous
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That's initially what I did, but I was receiving errors regarding "mismatched" types for the transducer output and the R1 resistor.  Any thoughts? Should I attach the project with the new layout?

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rola_264706
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Anthony if you are using the CY8CKIT-042-Ble and you are using the :Pioneer motherboard to power your PSOC Ble module then you selected the wrong pin for your project .  You can see that your pin selection is attached to the CapSense pins. See attached Picture.  I  unchecked the lock pin on your design and reran the build and it selected P3(4) . 

   

I was able to recompile it with out any warnings . I changed the transducer input to transducer_in. I have attached the project . I am running Psoc Creator 4.0 update 1 you are not so please update your Psoc Creator,

   

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Anonymous
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Bob, unfortunately I still can't get my project to compile after updating the PSoC creator.  When I unchecked the pin, and reran with auto-assign, I still was unable to build and the Creator still gave the error regarding mismatched types.

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Bob_Marlowe
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See attached project.

   

 

   

Bob

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Anonymous
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I cannot open the project..."This file would not be considered in the update process."  Never ran into this problem before.

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rola_264706
Level 8
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Here is your program again I changed your Analog pin to a TP and all is well.

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Anonymous
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I don't know what's going on with my PSoC Creator but I can't seem to open any of the attachments that you and other commenters have provided.  My apologies (any suggestions?)  I receive the message "This file would not be considered in the update process."

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Anonymous
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Errors found while loading "C:\Users\tbaldini.INSTECH\AppData\Local\Temp\Temp2_ADC_Tester-000.cywrk_.Archive02_0.zip\ADC_Tester.cydsn\TopDesign\TopDesign.cysch"  

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rola_264706
Level 8
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You must unzip the files and put them in a Dir . Use a different dir than you have been using. Windows has an unzip program so you don't have to download anything.

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Bob_Marlowe
Level 10
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You need to expand the archive before opening the project. Make sure you are using Creator 4.0 SP1

   

 

   

Bob

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Anonymous
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Using the Windows unzip program helped.  And I see now how the schematic should be made.  Previously I missed the whole point of off-chip components, which is why the whole "mismatched type" error occurred.  Makes sense now when I think about because what board possibly has an array of thousands of possible resistor values?

   

Thanks again, Anthony

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