• State
  • Locked Locked
  • Replies 28 replies
  • Subscribers 36 subscribers
  • Views 4180 views
  • Users 0 members are here
Support feedback
Options
Options
Related

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

How to increase clock frequency up to 120 MHz in TM4C1294 launchpad using internal PLL

Umesh Patil10
Intellectual 760 points
Other Parts Discussed in Thread: ENERGIA, MSP430G2553

Hello everyone,

i want to use TM4C1294 connected launchpad and Energia software for programming. In datasheet it is given that operating frequency is  120MHZ. So how to set it to 120MHz. and how much is by default frequency?

Another problem is that i want to handle analog signal up to 40 KHz with the same board. It is having 2 msps sampling rate. So with Energia environment; how much maximum sampling rate can we achieve practically?

thanks in advance...

  • 0
    TI__Guru 56685 points
    Moving to TM4C Forum.

    Regards,
    JH
  • 0
    TI__Guru**** 244400 points
    Hello Umesh,

    The power up settings for TM4C129x depends on flash content. If there is no flash content then it will run at 60MHz. If there is flash content and the SysCtlClockFreqSet is not called then it will be 16MHz PIOSC. Energia compiles with 120MHz so it should be set fine.

    Regards
    Amit
  • 0 in reply to Amit Ashara
    Intellectual 760 points
    Thanks Amit.

    Actually my aim is to find peak amplitude of analog signal coming from acoustic sensor which will be 40KHz and its random in nature.
    I am thinking that by setting one threshold value ; if i able to read 2 or 3 reading above that threshold then it will be near to the peak amplitude and i will able to find peak value. Previously i am using MSP430G2553 Launchpad with energia.
    Problem i am facing with MSP430G2553 Launchpad is that when the signal is above threshold; it enters in to loop to read the vaule again. I have execute loop 3 times and from that 3 reading i find out the max value. But due to slow execution of loop; max value is getting less than threshold value i.e. it passes the peak while executing the loop.

    So please how to solve this problem??
    If i use TM4C129x then can it be solve??
  • 0 in reply to Umesh Patil10
    Guru 20670 points
    I would try to describe more your objective, your attempt and your problem with greater detail.
    I get what you want to do, you want to find the highest value of a signal - but your attempt and how it failed is not clear enough
  • 0 in reply to Umesh Patil10
    Guru 47900 points

    Umesh Patil10 said:
    Actually my aim is to find peak amplitude of analog signal coming from acoustic sensor...

    Would it not prove far more efficient to state your, "Actual aim" w/in the very first post?   Any "actuality" should be presented in detail - so that responders are not forced to "guess and/or spin their wheels."

    Ask and ye shall (maybe) receive.   Delaying reality (or actuality) serves little purpose - seems poorly thought/considered...

  • 0 in reply to cb1
    Intellectual 760 points
    hello amit
    my code is like this


    int i, threshold=700, sensorValue= 0, maxValue=0;

    void setup()
    {
    Serial.begin(9600)
    }
    void loop()
    {
    sensorValue= analogRead(A3);

    if(sensorValue> threshold)
    {
    for(i=0; i<3; i++)
    {
    sensorValue= analogRead(A3);
    (sensorValue> maxValue)?maxValue=sensorValue: maxValue=maxValue;
    }
    }
    maxValue=0;
    }
  • 0 in reply to Umesh Patil10
    Intellectual 760 points
    hi luis
    from above code you can understand what is my problem while finding peak value
    when value is above threshold; i tried to take more value to reach max value but due to slow execution speed it passes the peak value and i am getting max value below threshold sometimes.
  • 0 in reply to Umesh Patil10
    TI__Guru**** 244400 points
    Hello Umesh,

    What is the nature of the analog signal?

    Regards
    Amit
  • 0 in reply to Amit Ashara
    Intellectual 760 points

    its nature is like current spikes coming with some noise and these spikes are coming continuously. But i am interested in its each peak value only. so to remove noise we have to set threshold but after that how to catch peak?

  • 0 in reply to Umesh Patil10
    Guru 47900 points
    Hello Amit,

    It would appear that the, "8 stepped sequence" would vastly improve poster's acquisition rate. Unknown is whether such can be achieved via Energia. (aka Inefficencia)
  • 0 in reply to cb1
    TI__Guru**** 244400 points
    Hello cb1,

    Based on the poster's last forum post, it seems that if the signal peaks between 2 conversions then it cannot be captured either.

    Regards
    Amit
  • 0 in reply to cb1
    Intellectual 760 points
    Another thing is i want to send data using bluetooth through UART. I tried for it but it won't work properly.
    I did it correctly on MSP430G2553 Launchpad but it was not working on TM4C1294 connected launchpad.
    is there any extra setting required due to more no of UART and multi function pins??
    Plz tell me how to do in Energia..

    Thanks..
  • 0 in reply to Umesh Patil10
    Guru 20670 points
    The tiva has multiple UART peripherals. You use Serial for the one connected to the USB-Serial converter which is UART0.
    Of course you need to choose which one your using if you use other than uart0.

    Quick search - first result...
    www.google.pt/webhp
  • 0 in reply to Amit Ashara
    Guru 117855 points

    Hi Amit,

    And happy 2016 in 14+ hours. (or so)

    My read of poster's work reveals only a single step conversion is achieved. Thus the ADC cannot convert at its highest rate - and "peaking" data surely may be missed. Achieving the highest possible - back to back to back conversions - to my mind - has the best chance to "capture" the elusive peak.

    A "real" ADC (believe you hinted at that) is far better equipped to make such captures.

    As always - the "soundness" of poster's issue & implementation and "interpretation" of what's "real" is unexplained - thus in doubt...   And - as we noted (more comprehensively) w/in another posting ("SD Card") poster's Subject is (hardly) representative of the meanderings w/in his post...  (i.e. post is far more aimed at ADC's frequency of captures than at MCU clock increase.)  

    Future, searching posters (or those vendor staff forced to "categorize") have NO CHANCE of properly classifying such posts in which the Subject so differs from post's central thrust.   Poster Guidance (again) provides the answer.  Unguided - not so much.  (i.e. not at all!) 

  • 0 in reply to Umesh Patil10
    Guru 10570 points
    That raises several questions

    First, how narrow are the peaks? I have a sneaking suspicion you have multimegahertz frequency content.
    Second, is the level you measure an ac or a dc level?
    Third, why have you rejected capturing the peak in analog? That reduces the load on the micro tremendously.

    Robert
  • 0 in reply to cb1_mobile
    TI__Guru**** 244400 points
    Hello cb1

    I suspect, that it is some energy envelope detection being planned and the details alludes us all.


    Regards
    Amit
  • 0 in reply to Amit Ashara
    Guru 47900 points

    Indeed Amit - and it is those "details" - almost "never" provided - which endlessly land upon these rocky (uncharted/unguided) shores.  

    Poster - while questioned under bright lights - did reveal, "acoustic sensor" - seems that a fairly simple "op-amp" configured as, "Sample/Hold Peak Detect," would meet the (unspecified) requirements.   It is always delightful when the post's "actuality" - emerges from its cocoon - only after a (too long) period of gestation...
     
    Never would we "hoist sails" w/out our sea charts - such precautions have value (far outside) water-craft...

  • 0 in reply to cb1
    Intellectual 760 points
    hello robert,
    peaks are very narrow and i am measuring ac level.
  • 0 in reply to Umesh Patil10
    Guru 10570 points
    That explains a lot. And question 3?

    Robert
  • 0 in reply to Umesh Patil10
    Guru 10570 points
    Also, how narrow is very narrow?

    Robert
  • 0 in reply to Robert Adsett72
    Intellectual 760 points
    yes it is very narrow
  • 0 in reply to Umesh Patil10
    Guru 10570 points
    When asking how narrow I was expecting a quantitative answer. I. e. Something like 6uS half width.

    Homework?

    Robert
  • 0 in reply to Robert Adsett72
    Guru 117855 points

    Robert Adsett72 said:
    When asking how narrow I was expecting a quantitative answer.

    New year dawns avec monsieur becoming, "Tres demanding" mais oui?   (staffs' eyes rolled (likely along w/yours) @ (definitive) "very narrow")

    Recall - this is an energia-based post - titled, "increasing Fclk via internal (one rarely expects an external) PLL."   Can this be - at all - real?

    Tool to task and background/experience/capability to desire/task... ... ... neither seem much in play...

    40KHz max (initial post) almost signals remote control band - and that's always well-handled w/digital techniques.

    Bonne annee, mon ami.

  • 0 in reply to Umesh Patil10
    Guru 92251 points

    Umesh Patil10 said:
    Actually my aim is to find peak amplitude of analog signal coming from acoustic sensor which will be 40KHz and its random in nature.

    Could you explain in more detail the application.

    1) What is the part number of the acoustic sensor and how is it interfaced to the TM4C1294 launchpad?

    2) Does the application use the acoustic sensor in "receive only" mode?

    3) Or is there a acoustic sensor transmit and receive pair, e.g. for proximity detection or flow rate measurement?

  • 0 in reply to cb1_mobile
    Guru 10570 points
    You should start the year with high expectations, mais non cb1?

    Happy New Year to you as well.

    Robert
  • 0 in reply to Robert Adsett72
    Guru 117855 points
    @Robert,

    Expectations - along w/signal widths - are "very" narrow! (that's completely clear - mais non, mon ami?)
  • 0 in reply to Robert Adsett72
    Intellectual 760 points
    Hello robert
    I dont know how to capture peak in analog signal

    and these peaks are coming continuosly like trigger pulse. So how can we capture all these peaks in analog signal?
    I dont know anything about it
  • 0 in reply to Umesh Patil10
    Guru 10570 points
    Your first step is to determine the signal characteristics.

    Hook up your oscilloscope and measure the width of the peaks and the frequency. Use any existing knowledge to help determine what is noise and what is signal.

    Robert