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52 Threads found on Square Wave Pic
Generating frequency modulated square waves is a completely different from replaying Audacity waveforms. Like betwixt I believe that any processor with hardware timer output can generate the intended tones with acceptable quality for an alarm siren. The "only" problem is to write suitable software. I also believe that insisting on (...)
[QUOTE=online79;inverter Please help me to generate 2 alternate pwm with variable duty (by preset) for a square wave inverter by those pic microcontroller, which have no hardware pwm. please guide me. For square wave inverter you need not require 2 alternate pwm. Only one pwm, be it hardware or software, (...)
I started R&D right after graduation in 1975 and discovered Crystal Oscillators (XO) had already been around for a long time and since CMOS came out, the best way back then for a 10~20MHz XO is still used today because of its low, cost, high quality square wave and low power for pic's and ATMEGA's etc. The configuration is called Pierce (...)
Dear MRahman sir i am new in this site, i want to make a square wave 50Hz IPS or INV I am well in Mikroc, Please help me sir . . . . . . . .
how to measure the frequency of square wave (time period=20us) and display the high and low period in lcd? i tried using capture mode and using counter but failed..... help me!!!
hello everyone I am trying to measure frequency using pic16f886. I am using simple comparator for Sine wave to square wave conversion. And I have attached the input of comparator with RA4/T0CLK to use Timer0 as a counter.I have also copied code for it but my LCD displays counts from 0-9 and then again roll overs to 0 and (...)
hi... need count square waveform input in pic16f877A...n that what pin to input waveform... help in Hi-tech compiler...experience guys...
I am searching how to make a DDS generator or reprogram the one like this. What I need is square and sine wave from 2-10V otput with programable set timer when DDS is off and frequency from 1Hz to 1Mhz can someone advice me how to do it? What is easiest and cheappest way? obr
Please Define the purpose of ZCS pulse. pulse width? Lag/lead? Polarity? Or just high or low if Vo<=x where x=<0.5V Two common solutions 1. A logic inverter can make sine > square wave {with ac couple and 1M feedback.} An XOR gate with small RC delay on 1 side can produce pulse for each transition. RC delay can be anything from <<1us to >
from pic micro controller i am generating 100khz square wave signal. i am feeding the square wave to 6n136 optocoupler but the output of optocoupler is phase inverted in order to correct it i am using 557 transistor. my doubt is can i use 557 transistor for switching 100khz frequency is there any other way. (...)
Provided it is enabled and connected correctly you should see a signal at both outputs, one virtually identical to the input and the other inverted. If you are measuring across the outputs you should see a square wave reversing in polarity. Brian.
Hello I experiment with a 50% duty cycle square wave generator on a pic16f84. I am using just a pin as a square wave output. Using a 4MHz crystal, how can I calculate the output frequency? My goal is to output 135-137KHz square wave signal. My code is below (...)
I presume "PWM" means in this case that a pic timer is used in PWM mode to generate a square wave of fixed duty cycle. We get a 5V square wave at the MOSFET drain (or less, depending on the LC values). It will generate an AC current through the LC circuit. If LC is tuned to 125 kHz, it's mostly a 125 kHz (...)
I am not able to give you the circuit becuase my proteus is does not has the components I am suing,but I have the pic 16f1827 whith which I am outputting a square wave which passes into the driver ICL7667 and then those the output of the drive go to the gate of the MOSFET ,but the MOSFET are becoming very hot,so I am asking if there is any (...)
Can some body plz help me to modify the following codes for counting the frequency up to 2Mhz of a square wave and sine wave: #include <16f877a.h> #use delay(clock=20M) #include #include #fuses hs,nowdt,nocpd,nolvp,noprotect #byte portc=0x07 #bit led=portc.4 void LCD_D(); unsigned int16 value; void (...)
Hi first, you should convert sine wave to a square wave with a simple OPAMP such as LM324 (has 4 OPAMP). Then you can count square wave using counter module in pic micro-controllers. good luck HR Karami
The bottom photo is not of a tachometer, it is a RPM simulator used to drive a tachometer by simulating the pulses from the ignition coil or electronic ignition module. The small IC you are referring to is certainly a level shifter or transceiver, not a 555 timer, as most automotive tachometers require/expect a 12V level signal from the ignition
A friend has a boat on which the rev counter reads very high since fitting a new alternator, it uses a feed from one of the coils to generate the display value. I'm thinking of a design to measure the frequency of the incoming sine wave, then generate a square wave of a lower frequency to drive the rev counter. In this case the ratio is (...)
Hello I'm newbie with pic. I would like to read 12.5 kHz square wave frequency from printer port output. This 12.5 kHz square wave have to be read by pic16F877A. If 12.5 kHz is read, then pic's output will be High. If 12.5 kHz isn't read, the output will be Low. Can (...)
Hello, I am trying to program an MCU in assembly to generate a square wave. I would like to achieve the maximum generated waveform frequency. The pic16f84A has an internal prescaler so driving it with a clock of 20MHz generates a much less frequency. Are there other microcontrollers (pic prefferred) which (...)
i want to convert a square wave with different period, the time that is sitting in 1 logic to be different and to belong to a combination of bits of code RC5, i know that is possible with pic 16f877 but i don t know how do it! thanks for help
Folks, I?d like to drive an H-bridge with 60Hz square waves with large dead time. This is for a DC to AC wonder. As long as pic's clock is no faster than 13.1Mhz, it should be possible to generate such slow waveform with ECCP. Right :?: Of course
TSOP1738 ~ SM0038 May should not work because we generate continuous pulse of IR at 38kHz rather than bursts of square wave with gaps. See dataheet: The data signal should fulfill the following condition: Carrier frequency should be close to center frequency of the bandpass (e.g. 38kHz). Burst length should be
But for alarm sound you do not have to make a since wave, simple square wave will also do fine.
C3 and C4 are part of a switched capacitor step-up converter. Drive the pic I/O pins connected to C3 and C4 with a high freq. (10Khz) square wave. If C3 is driven high C4 should be driven low and if C3 is driven low C4 should be driven high. That's all there is.
Hello, I changed caps to 47pF. It works better now. The start up time is up to 2 seconds. Thanks to everybody, especially to betwixt. But I am confused about the oscillator´s wave shape - I supposed the square wave but I have sinusoidal wave instead. Is it normal for such frequency please?
Hi every one I try to generate a square wave generators of 40 KHz, so i use a 18f4520 pic and write the following programmes : int y, yy; main() { do { portb=0x00; for(yy=0; yy<20; yy=yy+1) delay_us(1); portb = 0xff; for(yy=0; yy<20; yy=yy+1) (...)
Alright analog guru's I've got an issue. I need to take a 0 - 12v square wave of 50% duty cycle and varying frequency and produce a +/- 2.5v sine wave with 4 times the frequency of the square wave. I'd thought about using a pic to count the time between 2 incoming pulses, then on the third (...)
oups sorry it's sinewave I gave you... by the way it's better than square wave... regards,
I want to generate square wave oscillation using pic16F873A with fixed duty cycle say 50% but i want to be able to change the frequency of oscillation from 1Hz to 1MHz by keying in the required value and make the pic generate it. 20MHz crystal oscillator is used. pls, i need help on how to do this.
ic'S for this are few and far. There is difficulty getting a stable oscillator. waht about pic to give square wave which yuo filter with opamp filter to a sine wave?...then amplify it to what ever amplitude you want
can i use pic 16f877a to change the frequency on the output for square wave i need the user select the value of the frequency and diseply it on lcd :?::?::?:
For sinewave generation: MSLOSC from MSI For square wave generation: Linear Technology LTC6903 & LTC6904 All are small serially programmable chips.
how can i read 50Hz with pic. i am using pic basic plus but i cant use pulsin command for this purpose bcaz i my main loop i cant wait so long. can i read 50Hz square wave through interrupts if i use portb.0 for the hardware interrupt, i cant use CCP pin for capture purpose bcaz i am generating PWM with this pin. i am (...)
Can anyone pls tell me how to generate square wave using Timers rather than delay in pic microcontrollers (16F876). Im using CCS COMPILER. Regards.
11.0592MHz is usualy used in microcontroller systems or other systems that have UART communication. This frequency feeding the baud rate generator, permits baud generation with 0% error. On the market there are plenty 11.0592MHz quartz crystals - this is a "standard" frequency. Just design a quartz oscillator followed by a buffer gate with HCMOS
Hello everyone! just wondering if anyone has any ideas and/or examples on how to output an adjustable square wave in the range of 6hz-800hz using a pic16f818 running 8Mhz with the internal clock... Im using assembly Thanks! -Ryan
if u are going with square wave just use this output_high(pin_a0); delay_ms(10); output_low(pin_a0); delay_ms(10); this outputes the 50hz square wave. for sine wave u have to do the pwm.and use filter on the output.
Obviously, yes! But can be square wave, triangular wave, sine wave, arbitrary....
Hi, I wrote the following program for pic16f84A which outputs 2 offset square wave pulses on pins B0 and B1 at 22hz. I'm using an external osc at 32khz on both cases. I need to migrate this code to C8051F300 chip. I'm not very familiar with it yet, so any help is welcome. I'm guessing just a slight modification (headers) and some pin (...)
To receive this signal on any TV set you need a TV modulator, as these circuits (including pic-based with 2-resistor D/A from your last post) generate baseband video signal .. The rason why some TVs may pick-up 'something' is that this signal has a lot of harmonics (as any square wave has) but the high-order harmonics are (...)
Hello all. I'd like to introduce another idea. If you are sure that the wave shape is always the same, i.e., sinewave, I would propose that: square your input signal using for example a comparator or a smith-trigger gate as 4093 or 17132. Then connect the square signal to one of the CCP inputs of the microcontroller. (...)
Complete design of square wave inverter with PWM and output voltage correction on step basis and battery charger available with HEX code to program pic16F72. 250watt to 5kw design Data include pic code Schematic and parts list PCB Files Anybody interested can contact me on Cost apply for data tran
Hi. In the pic below I have a comparator circuit which I want to use to convert a sine wave into a square wave. As you can see, the circuit converts the sine wave and gives the resulting square wave the same frequency. But the square wave (...)
how to calculate the switch-capacitor's transfer function in a continuous system, it is controled by the output square-wave as a frequency to voltage.
Greetings Im kindly and desperately looking for a code to count the pulses from a square wave using a pic 16f872. i want these pulses to be the basis of varying the turn on time of a heater connected to the pic and switcing being done by a triac driver and triac.
I want to calculate True RMS(Root Means square) of square wave in Assembly Language of pic 16F72. For a pure square wave: 1. square waves: Like sine waves, square waves are described in (...)
Hello all I am not a prfect pic user, I used it one year ago in a project, but it took long time.. Now I want to do approximately simpler thing, but have no time indeed to waste in it.. I want to make a random number generator of variable bit rate I can discribe it in brief as follows: - It generates any random set of bits at one p
How clean is "clean"? I would consider an inexpensive DDS chip such as AD9834, or one of these: You will also need a clock oscillator, a low-pass filter (for the sinewave output), and a comparator (to convert the sinewave to square wave). The AD9834 includes a
If your input has a known waveshape, then you could measure a smaller portion of it and estimate the length of the full cycle. For example, if it's always a 50% duty cycle square wave, then you could measure half of it. If it's a clean sinewave, and you measure it with an A/D converter, then you could do a curve fit to (...)