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Everything posted by oPossum

  1. The useful life of an alkaline cell is about 1.55V (new) to 900 mV (under 10% capacity). At 1.25 volts there is still a lot of capacity left in the cell. So if you want to use the full capacity of two AA cells, then the circuit must operate on 1.8V to 3.1V. Low voltage boost converters that can boost a single AA/AAA/AAAA cell to 3.3V are becoming increasingly popular. Microchip (MCP1623/24/40), TI (TPS61220/21/22), and others make them.
  2. I don't think Rick posted it here. I did something similar for AVR and MSP430: http://forums.adafruit.com/viewtopic.php?f=24&t=5078 http://forum.43oh.com/topic/1375-characterize-dco-without-32768-khz-xtal/
  3. It is quite slow unless a power of 2 is used, for example n % 512 try 200000UL and 2000000UL
  4. Try this: const uint64_t RFREQ_INIT = ((uint64_t)(i2cInitBuf[2] & 0x3F) << 32) | ((uint32_t)i2cReadBuf[3] << 24) | ((uint32_t)i2cReadBuf[4] << 16) | ((uint16_t)i2cReadBuf[5] << 8) | i2cReadBuf[6]; const float FREQ_MHZ_INIT = (float)RFEQ_INIT / 268435456.0; // 268435456 = 2^28
  5. TUSB3410 is gone - that is the USB hub chip.
  6. Probably falls in to the category of "better than nothing" and "jack of all trades, master of none." The lack of an analog front end makes it non-competitive with a used good quality (Agilent or Tek) scope and/or spectrum analyzer. Can't do proper triggering without additional analog circuitry. Can't have accurate real time display without dedicated RAM for the FPGA. Same for the lack of proper filters and drivers on the analog outputs - can't compete with a proper AWG.
  7. Explanation of temperature sensor scaling math: http://forum.43oh.com/topic/1954-using-the-internal-temperature-sensor/ Some MSP430 have temperature calibration data: http://forum.43oh.com/topic/2027-how-to-use-temperature-calibration-data/
  8. The gate of the STP16NF06 should be driven with at least 8 volts. See figure 6 in the spec sheet. There aren't many MOSFETs that can be directly driven by the MSP430.
  9. This could be useful for a few projects I am working on. chibiace---------------------New Zealand Cubeberg---------------------USA JWoodrell--------------------Missouri, USA Rubi ------------------------Vienna, Austria Automate --------------------USA grahamf72--------------------Australia oPossum----------------------Secret Underground Bunker
  10. You can find them with this: http://forum.43oh.com/topic/1375-characterize-dco-without-32768-khz-xtal/ That doesn't write them to info memory, so you would have to write some code to do that.
  11. I think that the way you are looking at where the stack is located is different for CCS and GCC. For CCS you are looking at the start of the allocated stack space (0x03B0), but for GCC you are looking at what the stack pointer is initialized to (0x0400). The stack pointer is used as predecrement, so 0x0400 is correct. Try -Os
  12. Make sure you have the correct MSP430 specified on the command line. That is one possible cause of the stack being in the wrong place.
  13. They should bundle it with a heat gun, solder paste, and a Tiva chip. "Some assembly required"
  14. The mask is needed when RRA is used. Bit 15 is unmodified for both the 8 and 16 bit forms. It does not shift in a zero anywhere. CLC / RRC.B could be used to shift in zero bits. The 20 bit MSP430 have a limited barrel shift of up to 4 bits.
  15. oPossum


    Some pics here: http://forum.43oh.com/topic/2480-6-channel-logic-analyzer/ and here http://forum.43oh.com/topic/2499-logicboost-launchpad-mini-3-way-proto-pcbs-for-sale/
  16. oPossum


    The idea is that you only install what is needed for a specific application - it would rarely be fully populated. It is intentionally all thru-hole so anyone can assemble it.
  17. oPossum


    Eventually you will end up with this... http://forum.43oh.com/topic/2481-launchpad-mini-revision-3/ http://forum.43oh.com/topic/1599-diy-mini-launchpad/
  18. oPossum

    Set VCC

    He is serious. Maybe you have somehow conflated him with Wile E. Coyote. The voltage of the launchpad is not changeable via software.
  19. Select ACLK as the clock souce for the timer. ACLK defaults to the low frequency external xtal (typically 32.768 kHz). TA0CTL = TASSEL_1 | MC_1;
  20. oPossum

    WS2811 timing

    The timing of the data out of the WS2812 is interesting, but not what should be used by a microcontroller. The manufacturers specs should always be used. Sorry I didn't make that clear in IRC. WS2812 spec sheet attached. WS2812.pdf
  21. It's octal (for historical reasons) 011 == 9 == 0x09 == 0b00001001 == BIT3 | BIT0 BIT3 is the switch
  22. That happens when a vector is declared twice. Does not mean out of memory, but rather that two things want to be at the same address.
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