Reading multiple resistive sensors from PSoC 4 BLE Module

Tip / Sign in to post questions, reply, level up, and achieve exciting badges. Know more

cross mob
WeBa_2384626
Level 1
Level 1
First reply posted First question asked Welcome!

Hi everyone, 

I am using the CYBLE-222005 module to sending a resistive-based temperature sensor. Instead of building an external voltage divider circuit, I am using a current source (IDAC) that feeds a fixed small amount of current (< 300 μA) directly into the resistive sensor, and then I am reading the output change in RAW ADC and correlating it with the change in the resistance of my sensor which is acting as a variable resistor. 

Please check the schematic I am using below  

WhatsApp Image 2021-06-01 at 8.45.49 PM.jpeg

 

Now, I would like to actually expand it and sense form an array of 4 of that same resistive sensor at the same time, but I realized PSoC that I have only has two internal IDACs, so that might be limiting. 

The question is,  can use this same method to sense all 4 sensors at the same time. If so, what would be the arrangement? 

Can you please suggest a way in which I can measure 4 resistive-based sensors using CYBLE-222005? preferably using the internal components of the PSoC as much as possible 

Thank you and |I appreciate your help 

0 Likes
1 Solution
Vasanth
Moderator
Moderator
Moderator
250 sign-ins 500 solutions authored First question asked

Hi,

When you have connected the IDAC input to the ADC, AMUXBUS resource would have used for this purpose. Now you can write code to connect dynamically connect and disconnect pins to this bus to add multiple sensor inputs to ADC at different times. See CYDWR-> Analog Tab

 

Vasanth_0-1622625836537.png

Hover over the specific pins to see the registers to be written and mask for it to be connected to the amuxbus.

Best Regards,
Vasanth

View solution in original post

0 Likes
3 Replies
Vasanth
Moderator
Moderator
Moderator
250 sign-ins 500 solutions authored First question asked

Hi,

When you have connected the IDAC input to the ADC, AMUXBUS resource would have used for this purpose. Now you can write code to connect dynamically connect and disconnect pins to this bus to add multiple sensor inputs to ADC at different times. See CYDWR-> Analog Tab

 

Vasanth_0-1622625836537.png

Hover over the specific pins to see the registers to be written and mask for it to be connected to the amuxbus.

Best Regards,
Vasanth

0 Likes

Thank you, Vasanth. 

I have a question, in this case, will it be able to read from all 4 sensors simultaneously? 

0 Likes
Vasanth
Moderator
Moderator
Moderator
250 sign-ins 500 solutions authored First question asked

Hi,

Reading them simultaneously is not possible due to the hardware restrictions. You can do it in time-shared basis.

Best Regards,
Vasanth

0 Likes