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  1. J

    carbon steel screw versus brass screws

    So buy enough of them to make it worth the gas. These things are going to be hidden in walls surrounding your family and that's no place for for false economy.
  2. J

    rand function in AVR C

    You are 'return'ing from main()... don't know if that's THE problem, but it's hardly ever a good idea
  3. J

    Can't identify LED

    Here's someone who sells them... they don't seem like a lot of fun for tinkering, though
  4. J

    HM 10 range problem..?

    Have you set the power-level to +6dB? The default is 0dB
  5. J

    Effectively defeating PWM on Jeep Wrangler

    Here's a post that (if true- and it looks legit) might show what you're up against. A PWM rate sufficient for an incandescent load is way too slow for LEDs A fully nerded-out solution would: - read incoming PWM frequency AND duty-cycle (which might be 100%, dunno) - generate an output at a...
  6. J

    Dynamic FFT in VHDL

    I believe that the Fast Fourier Transform is fast partially because it requires the input data to be a power-of-two in length. Can you add zeros to your data to make it fit? This has always helped me with DSP concepts
  7. J

    2.4inch TFT LCD moudle 320 x 240 USART HMI GPU for Arduino DIY Component

    You have a Nextion display. Go read here and come back with very specific questions
  8. J

    mini christmas lights

    Consider how those serie-string lights work
  9. J

    C Programming

    I think the line that reads for(c=valor1;c=valor2;c++ ) should actually read as for(c=valor1;c>valor2;c++ ) .. this happens to me all the time. Some compilers can warn you about assignments appearing where logical tests are called for.
  10. J

    MC6802 "WAI" Instruction

    If the 6802 works like a 6809 ( a fair possibility) the WAI is being used as a synchronizer: it waits for a signal that WOULD interrupt, but for the SEI. Execution continues from that point with only 1-3 cycles(#?) of jitter. It's useful if you have only a few time-critical inputs.
  11. J

    Screamingly easy o-scope problem

    Those positions are usually 1x,10x and ground
  12. J

    Code execution in ISR too slow.

    If your microprocessor has two Input capture units, set them to capture opposite edges. No interrupt is necessary: do the calculation whenever the second capture-unit sets its flag.
  13. J

    MC6802 IRQ Pulse

    Well... d'oh. Misread the schematic, as has happened before. The 555 is indeed astable, and every time its output goes low, the instruction sequence: clr 0x2E rti ... occurs. Make of that what you can. Perhaps there is a peripheral at that address, although it is also in the on-board SRAM.
  14. J

    MC6802 IRQ Pulse

    The 555 is (re-)triggered every time a Valid Memory Address appears on the address-bus. If valid addresses are absent for 80 mSec, meaning the CPU is stalled, the IRQ is tripped. I think.
  15. J

    idle: driving steppers closed-loop?

    Printers use encoders. Saw an HP printer that used a 5"-diameter wheel (unenclosed!) being watched by a garden-variety opto-detector
  16. J

    Item Identification

    Heyco makes those... some folks just call 'em 'heycos'
  17. J

    Power for ws2812b and arduino

    By 'enable' I meant a control-line into the regulator that would disable it without the need for physical disconnection. This would be a function of the low-battery cutoff.. which you don't have. I don't know what you know, and so can't tell you to make your own, but here's a ready-made unit...
  18. J

    Power for ws2812b and arduino

    2 x 4M x 30-LED/M * .06A/LED is indeed 14.4 Amps. It's kinda hard to find a high-amp buck-regulator with an enable function: here's one the enable is described almost as an afterthought. You could use multiple regulators if on/off is easier to find in lower-wattage units. If you run into...
  19. J

    LED conversion

    Regarding your first picture: Is that assembly at the right something that you bought or something you made? It seems intended for the same socket as the halogen(?) lamp to its left. Does it have the LED driver built-in?
  20. J

    AV audio video red yellow white application

    The frequency-response of the video circuit might not go as low as you want for audio. But if you're happy with the sound, there's no harm done.
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