Pulse-Width Modulation (PWM) is a technique used for controlling the power given to electrical devices. The average power supplied is controlled by rapidly turning the supply on and off. Questions here concern driving PWM outputs from the Raspberry Pi.

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Noob project help, raspberry pi 2 controlling indoor growing environment [on hold]

im new to the raspberry pi world. I have raspberry pi 2 module b (the new one with 1g ram) that im not using. i want to use it to control indoor small growing environment. I have 4 x 12v pc fans that ...
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1answer
29 views

Can I use a GpioPin as a PWM pin safely on my Raspberry Pi 2?

Windows 10 IoT doesn't support use of the PWM functionality of Raspberry Pi 2. So, as a workaround, I'm planning on using a GPIO pin and just toggling it from High to Low REALLY FAST to achieve the ...
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3answers
39 views

What components are required for connecting servo motor to PI?

I'm planning to integrate a servo motor with a raspberry PI to press a switch button and found this post very helpful : PWM Control on Raspberry PI I'm considering this motor VicTsing Mini SG90 9g ...
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2answers
47 views

Two servos connected causes shaking

I have two servos which I want to control from my RPi. My problem is that the servos start shaking if I use them both. Both servos are connected to the +5V pin and to the ground of the Pi. So I have ...
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1answer
30 views

Why a resistance between signal and GPIO - External power source

I'm trying to power my servo from an external power source and control it with my Pi and I've found following circuit: http://razzpisampler.oreilly.com/images/rpck_1001.png Why is there a resistance ...
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2answers
54 views

Project needs multiple PWM

I'm working on a project that needs three (or more) PWM pins to work. But unlike Arduino, the Raspberry PI B+ has just one PWM pin. I've searched for solutions and I found that I can use the WiringPi ...
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48 views

Can't open pwm pin

I know there are many questions about using pwm pins in RPi, but nothing helpfull for me. Here is my code with described error: #include "pch.h" #include "MainPage.xaml.h" using namespace ...
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1answer
77 views

Raspberry Pi 2 B GPIO pwm and interrupt pins

Good day! I would like to use pwm and interrupt on raspberry GPIO pins but i don't know which GPIO pins are actually dedicated for pwm output and which is for hardware interrupts, is there a way for ...
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1answer
140 views

PWM control of motors with PHP front end

I have a dual H bridge connected to my Pi for controlling 2 brushed DC motors with. I intend to have a web interface to control the speed of the motors. I'm thinking of a HTML page submitting AJAX ...
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1answer
49 views

pigpio - set_PWM_dutycycle vs hardware_PWM

What is the difference between the set_PWM_dutycycle function and the hardware_PWM function in the pigpio python library when assuming the same frequency is set for both the functions. Will I get a ...
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1answer
104 views

Low-level PWM driver that works with the Raspberry Pi 2

Is there any low-level hardware PWM driver (such as RPIO.PWM or ServoBlaster) that is written in Python or C++ or Java (Python or Java preferred) and is compatible with the Raspberry Pi 2 model B?
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1answer
51 views

Output Accurate, Detailed PWM signal

I'm building a quadcopter using the RPI 2 Model B. I'm currently using the Pi4J library (Java library that wraps the WiringPi library) for my project. All is going well except my ESC (Electronic Speed ...
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1answer
31 views

pigpio PWM and ALSA

My Qt ( C++ ) application successfully dims the screen using the pigpio library on my Raspberry Pi compute module. It works great and is very stable using the code below. The problem, is that my ...
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2answers
174 views

ALSA - piezo buzzer directly on PWM pin?

Pre-empting the fact that the Raspberry Pi Zero has no analogue headphone jack - has anybody managed to setup the audio such that a Piezo Speaker directly attached to a GPIO PWM pin would make a ...
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2answers
127 views

Dimmer - How synchronize PWM with 230V power supply?

I need your's help with dimmer which is controlled by Raspberry PWM. My problem is lack of synchronization PWM with power supply. Unfortunately , I don't have oscilloscope waveforms to show my ...
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1answer
47 views

WiringPi - GPIO Output Vs PWM

So in the GPIO utility from WiringPi there is a command to change the mode of the GPIO pins. There is input mode, output mode and PWM mode. What is the difference between output mode and PWM mode? Is ...
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1answer
33 views

How can I send the same PWM output to multiple connections?

For a update to a small robot I am doing, I am controlling a robot using the Pi. This works very well but I would like to add more precise control, using PWM on the H bridge that controls the motors, ...
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3answers
339 views

3.5 mm jack starts to “hiss” after sound is played

I'm having the following issues with my amp on the Raspberry Pi 2, Model B. Boot up the Pi, everything sounds great. Play a sound byte through the Pi (using ALSA) Speakers hiss regardless of PCM ...
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1answer
83 views

Counting Pulse Length Using PiGPIO

Background I am trying to get a particle sensor to work with the Raspberry Pi (model B+). I am using the Shinyei PPD42N6 (datasheet here). The sensor outputs a digital signal with pulses ranging ...
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1answer
83 views

Count Pulses Width on RPi-GPIO

I have a Coin Acceptor, that sends a 30ms pulse when the coin was dropped. So I tried to use many codes, but I search in the net and I think the way is use PWM to read the pulse. But this doesnt work: ...
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3answers
108 views

PWM Fan causes clicking sound

I am using PWM to control the speed of the fan on my RPi 2. The problem is, when I am PWMing it, a clicking sound can be heard from the fan. I am using a 6v power supply for a 5v fan to compensate ...
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0answers
69 views

Run brushless motor with esc

I have looked all over the internet on how to run a brushless motor with an esc through RPi.GPIO and have no results. I have tried simply wiring the esc as it is supposed to be and programming it ...
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49 views

Controlling LED results in flicking

Using the amazing Pi-Blaster daemon I managed to control a connected RGB strip (to be exact: this particular one ...
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2answers
63 views

pwm fan on pin 18 help!

Can someone help me? I'm trying to control a fan using PWM and I cannot work out how to do it. This worked for a short amount of time and then stopped working. According to the docs, GPIO pin 18 ...
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2answers
194 views

Python - GPIO PWM control backlight LCD display

I want to manage an LCD HD44780 display connected trought my Raspberry Pi B+. The backlight pin (on Hd44780 display) need a resistor and I have 2 different display version, so the resistor value are ...
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27 views

how many external expander chips can the 5v output of the raspberry pi power?

I'm currently using PCA9685 gpio PWM and DO chip expander which can be powered by 5V . I'm currently powering it by using the 5V output on the raspberry pi . I would like to know how many of these ...
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1k views

PWM on Raspberry Pi 2 and Windows 10 Core IoT RTM

Now that windows 10 Core IoT - final RTM version is available, are there any concrete way how to program you Windows Universal App to use PWM hardware PINs ? I need this for controlling color of my ...
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1answer
61 views

dc motors not responding to gpio's

I have a question. I've attached dc motors to gpio's and after running python program it won't turn. Attaching LED's would make them light very low. Attaching both of them to pin 1 or pin 2 would make ...
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1answer
86 views

How to hide PWM.add_channel_pulse(dma_channel, gpio, start, width) output?

I use RPIO.PWM to control servos. All the time, the PWM.add_channel_pulse(dma_channel, gpio, start, width) method is called, text about the change is displayed (see image). I know there is a way ...
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93 views

Raspberry Pi ESC speed control

I've done ESC calibration using PWM from RPIO and set it's value to 2000 at first then 1000, after the long BIP it was set to go and when I set random value like 1300 or 1500 it would spin but only ...
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1answer
117 views

GPIO HW PWM @ 143Hz and 20-80% duty cycle, with WiringPi's gpio utility

I've tried to find the solution from other threads but they all seem to miss the point to a certain degree, usually going into kHz and MHz, or into the SW GPIO territory that I don't need. I have a ...
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1answer
98 views

RPIO.GPIO on RPie vers 1 B versus RPi.GPIO on Rpie vers 2B

With the "old" Pi v1 B, Python 2.7 (or Python 3.x.) I run a smal program for testing a servo motor. The motor opens/closes a lid on a smal fan. It worked fine, the servo not jittering. I was happy. ...
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1answer
47 views

Strongly typed language for the Raspberry Pi? [closed]

I would like to know if there is a matrix somewhere that list the languages that could be used on a Raspberry Pi. I've a broad experience in C# and a not to bad knowledge of Java. For my first weeks ...
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0answers
43 views

Controlling Stepper Motor Responding Strangely

I'm attempting to simply move a small stepper motor over GPIO using a Sparkfun Easy Driver. This Stepper motor is the one I'm attempting to use. I'm using similar code and configuration to that shown ...
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2answers
374 views

Max number of RC motors controlled by Raspberry PI

I have already searched the web, there are posts and articles showing how to control a servo motor or dc motor using raspberry pi. my question is what is maximum number of motors i can control using ...
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2answers
154 views

Is Raspberry Pi 2 better than Raspberry Pi B+ for controlling RGB LEDs via software PWM

Is the Raspberry Pi 2 better at controlling RGB LEDs then then Raspberry Pi B+ due to it being faster? Reason why I think this is because when I control my RGB LEDs I notice they change colour (both ...
3
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1answer
2k views

Using PWM in a Windows 10 App with the Raspberry Pi 2

I am a newbie an I have succesfully use a RBG Led, and I emulated PWM by code but it is too slow (and in somehow the timer autostops), Then I watched that the standard libraries support GPIO.PWM but ...
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1answer
679 views

ESC control by Raspberry Pi B to manage brushless motors via Python

This post may be similar to other ones, but they didn't solve my problem: I've got four Hobbywing Skywalker 40 A electronic speed controls (ESC), to control four brushless motors (these ones) to ...
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1answer
711 views

How to initialize an ESC with Python code [duplicate]

I can't make my brushless motor move; it kepps on beeping. I have connected it to an electronic speed control (ESC) and am trying to signal the ESC from the GPIO pins of Raspberry pi B+. How do I ...
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1answer
2k views

How to use pigpio to control a servo motor with a keyboard?

My aim is to be able to control a servo motor with my keyboard in a real time fashion using the python module of pigpio. That is, when I press say the 'w' key it rotates clockwise and when I press the ...
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1answer
112 views

how pifm pwm modulation works?

thanks in advance , i want to know how the pwm modulation of pifm works more precisely why the size of the buffer of data to be read in each iteration is 1024 bytes and how this buffer pcm data could ...
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1answer
224 views

Can I control this Pololu VNH5019 Motor Driver Carrier with a Raspberry Pi?

Do you see any reason why I should not be able to control this Pololu VNH5019 Motor Driver Carrier from a Raspberry Pi 2? So far I own neither an Arduino nor a Raspberry Pi, but I would like to build ...
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0answers
398 views

Multiple servo control RPi

I have written the following script to set positions for a single servo. import RPi.GPIO as GPIO import time #set up pin 11 as an output GPIO.setmode (GPIO.BOARD) GPIO.setup (11, GPIO.OUT) ...
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1answer
143 views

brushless motor speed control

I have successfully been able to turn the motors through the code pasted (found online). I am trying to adapt the code for a speed control, but it seems that the speed only goes to 100%, I have tried ...
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0answers
187 views

Raspberry pi with PS3 Controller

Hi I have used the following code for a specific movement for the servos. In my project I have 3 servos per nacelle (2 nacelles) to control the motions for the bicopter. I want to control the inputs ...
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1answer
307 views

RPi use in inverter

I am building a pure sine wave dc/ac inverter and looking at the possibility of using the Rpi to control the h-bridge. I need a sinusoidal encoded pwm signal at around 20kHz. So the pulses would ...
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168 views

Raspberry Pi with ESC and PS3 Controller

I am new to coding and I am trying to control ESCs through a PS3 controller which will be coded on the Raspberry Pi B+. I think this can be done, but i have read in a lot of places that I need to use ...
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1answer
499 views

Special PWM files are not found on Raspberry Pi 2

I just got my Raspberry Pi 2 B (V1.1) and wanted to fool around with the Sunfounder starter kit a bit. The "sunfounder kit" is a learning kit with a couple of electronic elements (bread-board, ...
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1answer
268 views

Raspberry Python Libraries

I am currently working with a Raspberry Pi (Model B+) and have some experience with Arduino (and it's derivates). Now, there are three Libs for GPIO access with Python for the Pi: WiringPi ...
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1answer
2k views

Creating a 0-10V voltage range for ballasts using Raspberry PI and amplifiers [closed]

I have been working on automating my house and i was looking to dim and brighten the lights (not only led) using ballasts which require input voltage of range 0 to 10v DC depending on which the light ...