PSoC 4 MCU

[Anonymous]

 In the comparator example they talk about placing an Analog MUX beofr ethe opamp, so as to calibrate and swirch between normal and the calibration operation. What exactly is the use? and what is the calibration they are referring to?

[JoMe_264151 · Accepted solution]

All signal paths transmit two kinds of signal mixed together: the signal you like to have and some unwanted signals. The latter consists of noise, offsets gain errors etc and is normally named "Errors". Calibration is a process to reduce some of those errors as gain errors and offsets. To reduce noise there are filters in use like a simple averaging filter which cancels noise in a defined frequency spectrum.

   

Calibration usually measures one or more precision known signals and re-calculates from the measured result the gain and offset to get the precise values. With these the measurement of the unknown signal is corrected to get a more precise result. To measure the different signal sources the analog MUX is needed.

       

Bob

[Anonymous]

 OKay thank you . Now i got it .

[JoMe_264151]

You are always welcome!

       

Bob

[ETRO_SSN583]

In any signal path you have errors due to -

       

1) Non linearities

   

2) Offsets

   

3) Common Mode presence

   

5) Supply PSRR

   

6) Device specific errors, like crossover in CMOS input stages, AB output stages

   

7) Noise. Averaging filters most effective on non-correlated noise. UP

   

designs tend to generate highly correlated noise sources.

   

😎 Pickup, EM fields

       

Some basic ap notes -

       

www.dropbox.com/s/2h96beh1fbvz4e2/noise_notes.zip

       

Regards, Dana.

[Anonymous]

 I tried combining the ADC, OPAMP and the UART modules together to try a small test program. But the program isnt running as expected, I am unable to recieve any data in the hyper terminal. Is it possible to do this using the BLE module if so how ??

[JoMe_264151]

Have a look at this thread and follow the documents.

       

Bob

[ETRO_SSN583]

This might help -

               

http://www.cypress.com/?id=5509 100 Projects in 100 Days with Bluetooth

   

http://www.cypress.com/?rID=102799&source=psoc4ble     FAQs

   

http://www.cypress.com/?rID=102512     AN91445 - Antenna Design Guide

   

http://www.cypress.com/?rID=102505     AN94020 - Getting Started with PRoC™ BLE

   

http://www.cypress.com/?rID=110007     AN92584 - Designing for Low Power and Estimating Battery Life for BLE Applications

   

http://www.cypress.com/?rID=109900     AN91162 - Creating a BLE Custom Profile

   

http://www.cypress.com/?rID=110107     AN91184 - PSoC 4 BLE - Designing BLE Applications

   

http://www.cypress.com/?rID=102504     AN91267 - Getting Started with PSoC® 4 BLE

       

http://www.cypress.com/?id=5509         

       

                   

       

https://github.com/cypresssemiconductorco/PSoC-4-BLE/tree/master/100_Projects_in_100_Days     Projects

           

Regards, Dana.

[Anonymous]

 I read through it and have got a hang of it . But could you tell me which all functions we need to call when are using the SAR ADC. By functions i mean , the ones that are not there in the datasheet ir API. I havent understood how exactly I should go about these .

[ETRO_SSN583]

Each component has a section in its datasheet that defines all the

   

APIs associated with that component, call names, parameters,

   

return values. Right click component and open its datasheet.

       

Is that what you are looking for ?

       

For BLE look at the 100 days projects, several use SAR and transmit

   

data back to PC.

       

Regards, Dana.

[Anonymous]

 Can you give me a some documents to understand use of interrupts of the ADC. I am finding it difficult to understand the code.

[Anonymous]

 What is the range status of an ADC????

   

 And why do we need to clear it .

[ETRO_SSN583]

Interrupts -

               

http://www.cypress.com/?rID=38267     AN54460 - PSoC® 3, PSoC 4, and PSoC 5LP Interrupts

   

http://www.cypress.com/?rID=95069     AN90799 - PSoC® 4 Interrupts

           

Regards, Dana.

[ETRO_SSN583]

The range of SAR is shown when you config it and is a function of the

   

reference you use. Both diff and single ended range are shown.

                   

Regards, Dana.

[Anonymous]

 Why exactly do we need to use the clock frequency option ? Like how is this related to the system clock, is it the prescaled value??

[JoMe_264151]

You may have a look into the explanations of the component clock in the datasheet of the ADC you use (right click on component, choose open datasheet). Have a look at the aclk-input description and the Clock Source explanations on page 5.

       

Bob

[Anonymous]

 Thanks a lot. It works fine now.

   

Now could you tell me how i can send this ADC value Via BLE to the phone. I need to just send it and also use LP mode .

   

what is th ebest example project to learn that ??

[Anonymous]

 What is the standard procedure to send and recieve data using BLE ??

   

Which all APi's are needed to perform the above functions , like it owuld be helpful if you could tell me what the detailed procedure would be .

[JoMe_264151]

There is probably no "best" way to do that, but there are several different ways with different behaveour.

   

I would suggest you to go through all the project examples in this blog and see how and what is sent/received between the BLE devices. There is always a .pdf documentation that you can read first to see if the projec fits to your interests.

   

Does "LP" in your previous post stand for "Low Power"?

   

if so, there is an application note concerning low power only.

       

Bob

[ETRO_SSN583]

Why exactly do we need to use the clock frequency option ? Like how is this related to the system clock, is it the prescaled value??

       

1) Clk internal or external simply user choice. Flexibility.

       

2) Go to the *.cydwr file in workspace explorer, clocks tab, you can see/config

   

various clks. The clck component doews have an api controled scaler. Right

   

click component......

                       

[Anonymous]

 Great thanks a lot . This is what i wanted form the clock part.

   

Yeah by Lp I meant Low Power . what I wanted is a tutorial to check the procudure to send data from the BLe(server, custom Profile) to the client (phone app Cysmart). I wanted to know the various steps involved .

[Anonymous]

 Th BLE module works as a peripheral and the phone as a CLient. So i wish to send data from the BLE module to the phone an dview it there. Her the phone initiates the connection and then th emodule sends the data to it.Could you walk me through the procudure to obtain the above mentioned scenario.

[Anonymous]

 cyBle_connHandle , What does this coommand do ?????

[Anonymous]

 Please check the application note AN91162 (www.cypress.com/?rID=109900 ) for details on how to setup BLE connection and send data between your module and BLE capable phone.

       

As for cyble_connHandle, it is not a function but rather a variable that stores the connection handle value after the connection between the devices has been successful. it is required by some APIs to communicate data to connected device.

[Anonymous]

 How do i send data from the BLE Module to the App?? The above  gives the method to recieve command from the app 

[Anonymous]

 Build error: The command 'arm-none-eabi-gcc.exe' failed with exit code '1'.

   

I am recieving this error . there are no errors in the program but there 5 warnings. 

   

What do i do 

[Anonymous]

Hey guys,

   

Could you tell me how to implement a feedback system in an opam p and then give this connection to the SDC also. It seems to show an error everytime i try it. 

   

I am using resistors extrenal to the board. The output of the opamp is given to the ADC. But when i trake a feedback it shows an error.

[ETRO_SSN583]

Schematic of what you have done ?

       

Most common problems -

       

1) You are using it as inverted output and not offsetting the

   

input to meet CM range for output.

       

2) You have positive feedback and it is actinbg like a comparator.

       

3) Too high a gain and offsets are being amped and saturating output.

       

Regards, Dana.

[Anonymous]

 How to use an opamp with a feedback in PsoC crester.????

   

No oputput obatined when used in this state.

[ETRO_SSN583]

Post an archive of your project -

               

“File”                                                             Creator

   

“Create Workspace Bundle”

           

Regards, Dana.

[ETRO_SSN583]

What is your ref into the OpAmp NI inout. Since this is an inverting

   

configuration, then "normally" it would be tied to some + Vref, and

   

your positive going input signal would make the output traverse

   

towards Vss.

       

The second OpAmp is not needed, the first provides the requisiste low

   

Z output into the SAR.

       

The T(s) relationship -

               

You can compute your CM range in and out easily br remembering the Inv and NI input of the OpAmp

   

are at Vref.