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Everything posted by Markers

  1. Hi, I have built an embedded product on a custom pcb that uses an MSP430G2553 communicating with a MMA8451 accellerometer via I2C, and flashing LEDs when certain acceleration events cause interrupts. The system works reasonably well but I want to add some post-interrupt code to verify the direction and intensity of the acceleration to avoid false positives. I can read the value in the relevant TRANSIENT_SRC register (0x1E) on the MMA8451 but the system hangs returning from the ISR. I placed a breakpoint in the closing curly bracket of the ISR, and when I stepped past this breakpoin
  2. Hi Jcjc, If your follow the response stream above you will see that I had to rename my User file to remove a space I had in my name. It was a bit of a pain but eventually it worked. Regards, Mark
  3. Hi Zeke, Yes, that is exactly what I have done, and the end result is exactly what I needed. Thanks again for your help. Cheers, Mark
  4. Hi again Zeke, I have found either a workaround or the correct solution (not sure which!): I addded "_bic_SR_register_on_exit(LPM3_bits);" to the end of both ISRs which I have never had to do before, but it is all working perfectly now. I'm very grateful for your help. Regards, Mark
  5. Hi Zeke, I have implemented your suggestions for Fired and Serviced flags outside of the ISRs but now the program will not fall into the while(1); loop at all after an interrupt. I know the program loops through the ISRs at the appropriate times but nothing else happens. Do you have any idea why this is happening? Thanks, Mark
  6. Hi Zeke, Many thanks for your prompt response. Yes, indeed it does help! I was concerned about all the activity in the ISRs but wasn't sure how to extract it. The printfs will certainly be removed once the prototype is stable, and I will tune the ACLK so that I get a consistent 1 minute loop. Finally, I have found the cause of the occasional error in the Timer ISR: if the process freezes for more that 1 minute (1 cycle) another Timer interrupt is created causing the program to run through the ISR and increment ++TThis. I will disable this spurious interrupt which should fix my
  7. Hi all. I have made a lot of progress on my project, and have only one issue eluding me at this stage of the prototyping It involves getting a timer interrupt and a button interrupt to work together. I have 3 key times T1, T2 and T3 that determine the actions: between time 0 and T1 nothing happens; between T1 and T2 the timer re-sets to zero and starts again; between T2 and T3, P1.6 flashes 10 times; and after T3 the timer must freeze where it is until a button interrupt re-sets the timer to zero and starts again. The code is attached. You will see I have implemented tiny_printf so
  8. Hi NurseBob. Thanks for your latest messages. The reference on low power design is great and will certainly help. You are correct in your assessment that l am "just getting into electronics" : I am 70 and a recently retired engineer and loving getting into hardware after decades of (self-taught) programming. Hence the sometimes naive questions! I have been using Dave Jones' blog which is very informative. Thanks again.
  9. Hi All, I think I have discovered something, but I'm not sure what! I noticed when I turned my LED desk lamp off the consumption rose, and fell again to it's ~12uA level when I turned it back on. Also, the LaunchPad was on my desk quite close to my laptop. I then dangled the LaunchPad over the edge of the desk on the USB cable (ie. in the shadow of the lamp, and below the level of the laptop), and the power consumption went down to a steady 0.6uA as in the Workshop video! The power consumption still shoots up if I move my hand close to the LaunchPad... Thanks for all your hel
  10. Hi Frida, Thanks - those are good thoughts. The Lab example has the following code which I assumed handles the inputs and outputs: void ConfigPins(void) { P1DIR = ~BIT3; // P1.3 input, others output P1OUT = 0; // clear output pins P2SEL = ~(BIT6 + BIT7); // P2.6 and 7 GPIO P2DIR |= BIT6 + BIT7; // P2.6 and 7 outputs P2OUT = 0; // clear output pins } Would that code not be sufficient to prevent noise from any un-t
  11. Hi Rei and NurseBob, Thanks for your responses. Rei, yes the green LED jumper is on, and no, the green LED pin is not shared - as per the Workshop video, the LaunchPad is stand-alone, only connected via the USB cable to the computer. NurseBob, I have tested the project in Release mode and the power consumption drops to about 10-17uA, but the reading fluctuates a fair amount. Interestingly, if I hover my hand over the top of the LaunchPad the power consumption goes up to 60-80uA but again very variable!? The vidoeo in the Workshop does not show such fluctuations, and I can't un
  12. Hi, I have been working through the MSP430G2553 Workshop and have just finished Lab 6. Running the code from Lab6c.txt in the supporting files does not give me quite the same results as in the video: the green LED does not come on, and the current draw on my Digitor Q1585 DMM shows about 20uA, not the 0.6uA I was expecting. Does anyone know whether my LaunchPads may be faulty (I have tried the example on 2 with the same results) or whether my DMM does not have a sufficiently low effective resistance? I am reluctant to continue with the Workshop until I am sure I will be able to
  13. Hi All, Many thanks for all your responses. NurseBob, you were right on the money: Energia was not installed. I re-installed it and everything is now working as it should. Many thanks! Mark
  14. Hi, I was working on an imported Energia project in CCS when I was informed that a software update to CCS was available. I installed the upgrade and restarted CCS in my project which now will not build. Instead I get the message "Buildfile generation error occurred.. Product 'energia.core' v18.0 is not currently installed and no compatible version is available. Please install this product or a compatible version. Build stopped.." My version of Energia is the latest (18). Can anyone help please! Thanks, Mark
  15. Thanks Rei. Wish I had known before I wasted money on three 2553s.
  16. Hi Fmilburn, Thank you so much for your thoughtful and helpful post - some real advice for a change! All the microcontrollers seem to be working, and all successfully flash LEDs and other simple tasks. I was wondering whether I had damaged some other components on the Launchpad other than the microcontroller... Its just the serial monitor and communications with the accelerometer that are causing me grief. I will look to upgrading to a newer Launchpad and try again! Many thanks, Mark
  17. I have checked the pin maps! Mine is a very 1.5, so the jumpers are at right angles. I note that the forums are bursting with people who have serial monitor problems, but no solutions beyond the jumpers. This must be a known problem... I have also deleted and reinstalled CCS and Energia several times. What else is there? Have I destroyed 2 Launchpads?
  18. Rei, My problems seem to be growing. I have gone back to basics to try and get my project working, and this involves writing values to the serial monitor with Serial.println(). For some reason, even with the TX/RX jumpers reversed, I am having a real problem getting anything to display. I have 3 different, new MSP430G2553 Launchpads and only one of these prints to the serial monitor, and even that not consistently. Is it possible that I have damaged the other 2 Launchpads? I am now seriously considering the wisdom of choosing the MSP430 platform - can't serial print and can't com
  19. Rei, No, I have not started my own thread - is that what is required? Mark
  20. Hi Rei, Thanks for your response. I have visited that link many times but the info is a bit sparse, and has not helped me. Do you have any more specific advice please? Thanks, Mark
  21. Hi, I have a similar problem. I have successfully built a simple game based on the MMA8451 accelerometer breakout board from Adafruit with an Arduino Uno. I am now trying to convert the game to a Ti Launchpad using an MSP430G2553 processor but cannot communicate with the MMA8451 at all. I have gone back to basics using the MMA8451demo.ino code (https://learn.adafruit.com/adafruit-mma8451-accelerometer-breakout/) in the Energia IDE with the MSP430 using pins P1_6 (SCL) and P1_7 (SDA) both with and without added 4K7 pullup resistors, and, although the programme compiles and ru
  22. Hi all, I am well underway with the MSP430G2553 Launchpad developing my game. Battery life is now an issue I have to address, and for this I have built in a photo resistor sensor that I want to use to put the processor to deep sleep when it is dark. Trouble is, I have no idea how to achieve this without keeping the processor awake to monitor the sensor! Is it possible to generate an interrupt from the sensor that suppresses all other interrupts until it is light enough for the game to commence? Some help will be greatly appreciated! Thanks, Mark
  23. Hi Jazz, Thanks for your comprehensive response! I will continue developing on my MSP430G2553 using your hints earlier concerning LPM3 with ACLK active. Are you confident that I will be able to port to a smaller form factor chip when we get to prototyping? Thanks, Mark
  24. Hi Jazz, Thanks, I had thought that would be the case. However, I am overwhelmed by the choice of MSP430 chips. Any suggestions? Mark
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