Thanks Steve. That is what I did. I copied the Msp430ClockP.nc into the application directory and changed the line setting the BCSCTL2 register and I set the constant TARGET_DCO_KHZ = 8192. It doesn't change the application execution time. Are you sure about the utility of the Rosc? I still think the external Rosc can increase the CPU clock. The msp430f1116 data sheet states that DCO frequency is higher with DCOR=1 in comparison to the configuration with DCOR=0 (page 37: DCO when using ROSC).
I also tried to set the DCO to the maximal possible frequency (I used the set_dco_calib(int calib) function from the Msp430ClockP.nc ) and still the time of running the code does not change. Any other suggestions? regards, Szymon ----- Original Message ----- From: "Steve McKown" <[EMAIL PROTECTED]> To: <[email protected]> Cc: "Szymon Fedor" <[EMAIL PROTECTED]> Sent: Thursday, February 15, 2007 10:37 PM Subject: Re: [Tinyos-help] Tmote CPU clock speed > HI Syzmon, > > On Thursday 15 February 2007 15:07, Szymon Fedor wrote: > > Does anyone know how to increase the default speed of CPU clock in Tmote? I > > tried to enable the external Rosc by changing the Msp430ClockP.nc file > > > > BCSCTL2 = DIVS1 | DCOR; > > > > and the time of executing some code (long "for loop") doesn't change in > > comparison to the default configuration. I am using the new Tmotes which > > have Rosc. > > The DCOR only tells the msp430 that an external DCO oscillator resistor is > present. The external resistor can improve the accuracy of the DCO, but > isn't really involved in setting the clock speed. > > If you are using tos2, the clock speed is set in Msp430ClockP.nc (probably > within /opt/tinyos-2.x/tos/chips/msp430/timer, depending on installation). > Check out busyCalibrateDco() and note the enum TARGET_DCO_KHZ. There might > be side effects to deal with. For example, defaultInitTimerA() should be > changed so that SMCLK stays at 1MHz because other components assume it is. > > Perhaps you know this trick already. You can copy this file to your project > directory (the directory you are in when you type "make tmote"). The local > copy of the file will take precedence over the one > under /opt/tinyos-2.x/tos/chips/msp430/timer. > > Have fun, > Steve _______________________________________________ Tinyos-help mailing list [email protected] https://mail.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help
