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Everything posted by oPossum

  1. Sparkfun's library if full of bad stuff. I know many people have been burned by it. Adafruit may be too. Best to do your own parts. Here is my battery lib with SMD & thru hole CR2032 holders drawn to mfg spec. http://www.memoryprotectiondevices.com/datasheets/BHX1-2032-SM-datasheet.pdf my_battery.lbr
  2. There has to be some source resistance ahead of the TVS or it's max current will be exceeded and it will fail or be damaged. TVS are tough devices, but they have limits that must not be exceeded.
  3. Ahhh --- there should be no solder mask under the entire battery area (~25 mm dia) and the contact pad should be no larger than 8 mm dia/square to ensure good contact.
  4. Ballast resistor is a good idea. An LM7806 (yes there is such a thing) would also work. The LP2989 would be happy with 6V in because it is a LDO.
  5. 12V - 5V = 7V 7V * 0.5A = 3.5W So you need a heatsink that will get rid of that 3.5 watts with acceptable temperature rise. It's in a SOIC package, so that's not really possible. So... use a TO-220 package regulator with a heatsink or a switching regulator.
  6. Maybe you could design the PCB to allow for an LED bubble display or a 1x8 LCD display. The LCD would be less authentic, but allow for better battery life and better readability under bright light. http://www.mouser.com/ds/2/291/NHD-0108FZ-RN-YBW-33152.pdf
  7. TEquipment.net ships to Canada and is reputable. http://www.tequipment.net/RigolDS1074Z.html?v=7401
  8. DS1000Z series has intensity grading ('digital phosphor'), faster screen updates, ethernet, serial decode options, optional function generator. It is comparable to the Agilent 2000 series in many ways. It has the look and feel of an analog 'scope - something very difficult to do with digital. The E series was great 5 years ago, but today it's like a toy compared to the Z series.
  9. Rigol DS1104Z - it's in a whole different class than the old DS1102E/DS1052E. Amazing performance for the price. It surpasses the 2000 series in some ways. Four channels so you can look at all the popular serial digital buses.
  10. I typically use them in for() and while() loops when the code may be ported to another architecture.
  11. The only fuse MSP430 have is code protect. Once you blow it there is no going back. Requires the MSP-FET430UIF to blow it - not supported by the launchpad.
  12. Parallax Propeller - 8 cores! Quickstart board is nice. Microchip PIC - 8, 16 & 32 bit Get a PICKit3 and choose a chip -or- the Microstick II if you want a dev board.
  13. When the max value is less than 2^8 (256): uint_fast8_t When the max value is less than 2^16 (65536): uint_fast16_t When the max value is less than 2^32 (4,294,967,296): uint_fast32_t When the max value is less than 2^64 (aprox 1.8E19): uint_fast64_t These fast variants will be promoted to the best suitable integer type. That will typically be an integer multiple of the register width. So on the MSP430, uint_fast8_t becomes unsigned [16 bit]. On x86 it would be 16, 32 or 64 bits depending on target operating mode. This doesn't matter much on the MSP430, but it does on some others su
  14. This may work for getting the stack pointer... unsigned * get_sp(void) { unsigned n; return &n; }
  15. #include <msp430.h> #include <stdint.h> static const unsigned long smclk_freq = 16000000UL; // SMCLK frequency in hertz static const unsigned long bps = 9600UL; // Async serial bit rate static uint32_t upd = 0; // Ultrasonic Pulse Duration (500 ns resolution) // #pragma vector = TIMER1_A1_VECTOR // Timer 1A vectored interrupt __interrupt void timer1_a1_isr(void) // { // static uint32_
  16. If that's not a typo - then it is probably way to high for the MSP430 to count reliably. You should have a front end circuit that presents a 16 MHz max square wave to the MSP430. Here is a simple frequency counter that uses Timer A0 to do the counting, and the watchdog timer as the gate timer: http://forum.43oh.com/topic/1913-frequency-counter-using-launchpad-nokia-5110-lcd/ The bottom half of main() is the code that does the counting.
  17. Apple G5 PowerMac (PCI version, circa 2004) There where also several other TI chips for power management and firewire on the huge motherboard.
  18. Generate PPM with the MSP430, and then convert it to multiple PWM with a CD4017. http://forum.43oh.com/topic/1226-rcremote-can-also-be-used-to-control-8-servos/ Thanks for sharing your project!
  19. OK, set a breakpoint in the ISR to determine if the timer setup is working properly. There may be some difference in the Tiva PWM vs the Stellaris PWM that is the problem. I don't have a Tiva LP, so can't test it myself.
  20. Does the green LED blink?
  21. Ordinary ceramic monolithic caps. Make sure your LCD module does not have a pullup resistor on the reset line - some do, some don't. If it does, you will have to remove it. The LCD reset circuit used by this project will not work with a pullup resistor on the LCD reset line.
  22. It is easy to calculate the register settings in your code... http://forum.43oh.com/topic/1973-usci-uart-bit-rate-setting/
  23. CS will enforce SPI sync. If CS is not used then you must make sure the SPI clock is perfect. If the LCD has not fully reset when SPI comms begin, then sync is messed up.
  24. Try adding some delays to reset. // Reset LCD DISPLAY_PORT |= RES; // Pull Reset High to Known State, Probably Unneeded DISPLAY_PORT &= ~RES; // Pull Reset Low to Reset LCD __delay_cycles(100000); DISPLAY_PORT |= RES; // Pull Reset High to Complete Reset __delay_cycles(100000);
  25. Something changed in CCS 5 and has broken some the of asm code I have written. I am porting an old project from F5418A/CCS4 to F5529/CCS5 so I may discover the problem soon (a few weeks).
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