SM470R1B1M-HT power saving methods.

Hi Wade,

Thanks for your reply,

I am not using ZPLL feature, I have disabled it with PLLDIS pin(pin.57). I am using 7.5MHz crystal oscillator. i am using RAM configuration not flash. the code which i am trying is posted below

#include <intrinsics.h>
#include <TexasInstruments/iotms470r1b1m.h>
#include <TexasInstruments/tms470r1B1m_bit_definitions.h>

unsigned int Delay_H;      // Internal high-byte

void startTimer(unsigned int _delay);


int main(void)
{

  // Set up peripheral registers.
  // First disable interrupts.

  __disable_interrupt();

  // Setup system.
 
 // GCR &= ~ZPLL_MULT4;                 //no multiplication because PLLDIS is disabled
  GCR &= ~ZPLL_CLK_DIV_PRE1; 
  GCR &= ~ZPLL_CLK_DIV_PRE2;
  GCR &= ~ZPLL_CLK_DIV_PRE3;                       // SYSCLK = fOSC/1 =7.5
  PCR = CLKDIV_1;                                               // ICLK = SYSCLK
  PCR |= PENABLE;                                              // enable peripherals
  CLKCNTL |= CLKDIR | CLKSR_ICLK;
  REQMASK = (1 << CIM_COMP1);                     // Enable SPI Interrupt mask

  // Setup periodic interrupt using RTI with RTICMP1
  RTICNTEN = CNTEN_NOCNT;                       // Stop counting
  RTICNTR = 0x00;                                             // clear 21-bits CNTR

  // Setup periodic interrupt timer
  // CMP1 used to generate  interrupt at every one sec.
  RTIPCTL = 2047;                         // preload 11-bits MOD
  RTICMP1 = 3600;                        // every one sec interrupt
  RTICNTL = 0x00;                        // clear and disable tap

  // interrupt control, clear CMP1 and enable CMP1 interrupt
  RTICINT = 0x00;
  RTICINT |= CMP1ENA;
  
  __enable_interrupt();                 // Enable Interrupts

   RTICNTR = 0x00;

  startTimer(10000);      // 1= 1 sec, 10000=10000sec=2.7 hour in standby mode

// Loop forever.
  while (1)
  {
      
  }
}

  //------------------------------------------------------------------------------
// TMS470R1B1M Standard Interrupt Handler
//------------------------------------------------------------------------------

__irq __arm void IRQ_Handler(void)
{
   switch((0xff & IRQIVEC)-1)
  {
   case CIM_COMP1  : 

    RTICINT &= ~CMP1FLAG;   // interrupt control, clear CMP1
    RTICNTR = 0x00; 
   
    if(Delay_H != 0){
        Delay_H--;          // Decrement time counter
     }else{            
        RTICNTEN = CNTEN_NOCNT;                       // Stop counting
        CLKCNTL |= LPM_RUN;
        }
    break;

  }
}

void startTimer(unsigned int _delay){
    Delay_H = _delay;
                 //
  RTICNTR = 0x00;                               // clear 21-bits CNTR
  RTICNTEN = CNTEN_UP;                         // Start count, CNTR and MOD will count in both USER and SYSTEM mode 

  CLKCNTL |= LPM_STANDBY;                      //Activate standby mode after starting RTI counter up
}

I have RTI settings to generate interrupt at every sec, the counter will decrese from 10000 to 0 to stop the RTI and exit from standby mode. any suggestions?

Regards,

Pavan.

Hi wade ,

Any suggestions on power saving methods. My method is wrong?

Regards.

Pavan.

Thanks Shawn.

Pavan, I believe it will also be necessary to disconnect from the debugger.  You will need to provide power from the DC jack vs emulator power.

Regards,

Wade

Hi Wade,  Michel james,

Thanks for you reply, 

This time i have connected my designed board with DC power instead of trying on IAR Stater kit.  I have proper DC supply.  I tried to put in standby mode not into halt mode.

My board is taking 65 mA current consumption, when i put controller in reset then it is consuming 17mA so it seems controller is taking remaining 48mA. I am trying to put in stand by mode.

CLKCNTL |= CLKDIR + CLKSR_ICLK + LPM_STANDBY;                               // Standby mode

dummy=CLKCNTL;

I tried to program into RAM and as well Flash. 

When i programmed into RAM, i am adding only above two lines in my main function. as well I am toggling one of the I/O pin for checking purpose after those two lines.  It didn't enter into standby mode because still it is toggling I/O and i didn't see any lower power consumption, but this time i have connected debugger. Once programmed into RAM then i removed debugger without powering off then also its same. If tried to program once again it is showing unable to halt CPU message, then I have to reset the controller to program once again.

When i tried to program same code into "flash" then, I think it entered into standby mode because I/O pin is not toggling but i didn't see any reduction in power consumption. It is same. Then i removed debugger and powered even it is still same power consumption as well it is not toggling the I/O pin but the strange thing is once I programmed to flash with Power saving code then I am not able to erase or program new active application, It was showing "unable to halt CPU abort debug session" message. I can't program into RAM as well after that. 

I am trying to put into "standby mode" then why it is entering into HALT mode. I didn't understand. It seems as per your information i lost two controllers. I didn't understand how to protect controller when i program into flash. I am not changing any thing and i don't have any other code only running power saving code and I/O toggling.

Max I am toggling I/O pin to know it entered into standby mode or not. 

Regards,

Pavan.

Hi shawn,

Thanks for your reply, 

I am using the same code but I have some doubts, At what frequency you running, my SYSCLK is 7.5MHz, I am not using ZPLL, will that influence? 

if i understand properly you are not running power saving code in flash? you running it in RAM. We can't use this code in flash? I have tried and lost two controllers after that.

Do we need set that GCR | = FLCONFIG ; after power saving code. 

If you don't mind can you explain me what values you using for  PSLEEP_MAX, PSTDBY_MAX, BSTDBY_MAX, BSLEEP_MAX. I am using default.

Regards,

Pavan.

Hi Shawn,

Thank you very much for your reply,

I am able to put into Standby Mode finally with your help and I used the same code which you posted. Upto now i worked with RAM programming. I am able to save power. I have one more question if you don't mine can you suggest me.

1) If i run the same code with flash programming, do i need to change anything or i can call the same function in main function and run as it is? I mean form the datasheet as it mentioned we have to run it from RAM even we use flash configuration. do we have to configure anything to run this function in RAM while programming through flash?

Regards,

Pavan.

Hi pavan,

You need to use specific instruction toindicate to the compiler wich part of the code is in Flash and wiich part is in RAM. Ram section will be automatically initialised at startup by the low level function provided by IAR.

It is not difficult but may take time to get it right.

Good luck

JM

Hi James ,

Thanks for your reply,
I am new to this kind of programming , if possible can you provide any example on how to do this.?

Regards,
Pavan.

Hello Pavan,

Are you testing the processor at temperature ?

Did you disable the flash memory ( and run from ram ?)

JM

Hi Pavan,

Is it possible that some of your surrounding logic is consuming the extra power?  In reset, all of the  pins of the SM470 go to a high impedance state.  However, I believe in low power mode the pins retain whatever state they were in before entering low power mode. I'm not positive about that, but I believe that is the case.  If those pins are enabling some external logic during low power mode, then maybe your extra power is going there. 

-Shawn

Hi JM,

I am not testing processor at high temperature, only testing at room temperature. I am disabling the flash as well.

Regards,

Pavan.