Search:

Type: Posts; User: std_match

Page 1 of 20 1 2 3 4

Search: Search took 0.03 seconds.

  1. Closed: Re: How to assign bit values at once to different port pins of different I/O ports?

    I suggest that you do it with a function. Call it set_leds(uint8_t led_bits) or similar. The function can easily extract the bits for each output port.
  2. Closed: Re: How to assign bit values at once to different port pins of different I/O ports?

    The processor can only write to one port at a time. Why do you want to hide this fact from the programmer?
    There is no generic way to do this, but for a few ports with the registers at contiguouos...
  3. Replies
    3
    Views
    436

    Closed: Re: Free image fro PYNQ Z1

    The images can be downloaded for free from Xilinx, but you must have an account and you must specify your geographic location.
    The is probably the safe way for Xilinx to comply with the US export...
  4. Replies
    3
    Views
    279

    Closed: Re: LT3750 Capacitor Charging Problem

    Make sure that you have connected the transformer with the correct polarity of the windings.
    The output should go negative when the MOSFET is switched on, and the capacitor is charged via the diode...
  5. Replies
    3
    Views
    569

    Closed: Re: I/Q baseband Modulator Demodulator

    In this case I/Q-modulation is overkill, but I think it can be used to create any modulation.
    BPSK is easy to do, just set Q=0 and change I between +1 and -1 according to the data bits.
    A more...
  6. Closed: Re: 0-100uA analogue meter (needle) to show 0-10v

    The series resistor should be less than 100k.
    You must subtract the meter's internal resistance from the theoretical 100k value (10V/100uA).
    In other words, the series resistor and the meter in...
  7. Closed: Re: Bilinear switched capacitor resistor equivalent resistance

    Charge is transferred to the output also when s1 is closed. What you describe happens 2 times per clock cycle.
  8. Replies
    2
    Views
    417

    Closed: Re: Latchup Caused by diodes

    A thyristor can be modelled as two transistors that keep each other saturated. This can't happen if you replace one of the transistors with a diode.
    A thyristor is not an arbitrary PNPN structure....
  9. Replies
    34
    Views
    2,240

    Closed: Re: Flyback controller explain

    The output voltage will probably be wrong, and it will change when the input voltage changes.
    You can check with a scope that the diodes on the secondary side conduct when the switch on the primary...
  10. Closed: Re: [PIC] MikroC for PIC32 PIC32MZ MCU Clock Frquency [MHz] bug?

    Look in the compiler manual. Some delay functions are based on the "oscillator frequency" and some other delay functions are based on the "MCU clock".
    Delay_ms is based on "oscillator frequency", so...
  11. Closed: Re: 2:1 Multiplexer with open drain Outputs IC

    I think it would be better to use a MUX on the signal going to the TDO pin on the connector.
    If you need to disconnect the ASIC TDI pin when the ASIC is bypassed, use another mux before the 3.3V to...
  12. Closed: Re: 2:1 Multiplexer with open drain Outputs IC

    The original request can be solved with a single 74HC4066 and 4 resistors:

    156598

    The unmarked resistors should not be critikal. Use 10K or whatever.
    The 1k resistor will affect the maximum...
  13. Replies
    16
    Views
    1,178

    [SOLVED]Closed: Re: fixed point arithmetic in c

    The two's complement format is good for addition/subtraction, but bad for multiplication/division.
    You want to multiply Q1.15 values 23166 (0.707) with 65535 (-0.0003)
    The simplest solution is to...
  14. Replies
    9
    Views
    667

    Closed: Re: instruction set translator

    This is probably not a small assignment.

    It is easy for the 8086 to emulate the 8051.
    It is very difficult for the 8051 to emulate the 8086.

    If you already have the EPROM contents, only...
  15. Closed: Re: Regulating temperature of mains connected heating element: Skipping mains half cy

    The commercial products I have seen use a fixed cycle time of about 40 seconds. The regulation is done by changing the "on" time while keeping the cycle time constant.
  16. Replies
    20
    Views
    1,110

    Closed: Re: Where does this equation come from?

    There is pseudo C-code in this article:
    https://www.edn.com/design/signal-processing-dsp/4006766/Tutorial-Software-implementation-of-Trigonometric-Functions-using-a-CORDIC-algorithm
  17. Replies
    20
    Views
    1,110

    Closed: Re: Where does this equation come from?

    That is probably only true if you have a hardware multiplier available with enough number of bits. One feature of the CORDIC algorithm is that there is no multiplication involved. Only shift, add,...
  18. Replies
    20
    Views
    1,110

    Closed: Re: Where does this equation come from?

    That range is enough since you can always use other ranges by simple trigonometric identities.
    However, it should be possible to extend the vector algorithm to +/- pi by adding new first rotations...
  19. Replies
    20
    Views
    1,110

    Closed: Re: Where does this equation come from?

    In vectoring mode (page 5), if you start with (x, y) values corresponding to 30 degress, yi will be negative after the first rotation, since the first rotation is 45 degrees. Every rotation will...
  20. Replies
    20
    Views
    1,110

    Closed: Re: Where does this equation come from?

    The logic is that the vector is always rotated in the direction that gets yi closer to zero.
  21. Closed: Re: NPN having its VBE protected against reverse voltage....but unecessary?

    I would never allow a transistor to go into "reverse VBE zener mode" unless that is the intended operation. It can permanently reduce the gain of the transistor, as dick_freebird mentions in post #3....
  22. Replies
    7
    Views
    728

    Closed: Re: Logic duplication and optimization

    I would probably use "Method 2".
    I will be confident that the synthesis result is optimal.
    I will be able to see the intermediate sum "a+b" in the simulator, and easily connect it to...
  23. Replies
    18
    Views
    1,641

    [SOLVED]Closed: Re: Protect FPGA Pin from negative voltage

    You must also look at the Vf/If diagram. To keep Vf below 0.5V, the current can only be a few tens of mA.
    I suggest that you make sure that the current in the diode never exceeds 1-10 mA (you select...
  24. Replies
    18
    Views
    1,641

    [SOLVED]Closed: Re: Protect FPGA Pin from negative voltage

    BAT54 directly between the FPGA pin and GND. The resistor is only necessary if the current through the BAT54 will be too high (set the limit somewhere in the range 1-10mA) without it.
    The resistor...
  25. Closed: Re: 1200 baud data transfer over audio passband of cellphone. Is that possible?

    Landline phone stations transferred the actual audio samples with 8 bits non-linear sampling at 8 kHz = 64 kbits/s.
    Cell phones tries to get similar audio quality with a much lower bit rate. To...
Results 1 to 25 of 500
Page 1 of 20 1 2 3 4