pi-fast-gpio

    0.1.0 • Public • Published

    pi-fast-gpio

    Super fast GPIO access on the Raspberry Pi using the pigpio daemon (for pwm, servo control, etc)

    The pigpio library uses direct memory access (DMA) to allow you to sample the GPIOs up to 1,000,000 times per second. It also makes it fast enough to give you PWM and servo control on all GPIOs simultaneously. The servo waveforms are accurate to a few microseconds.

    This code is based off of the python library included with the pigpio download.

    Installation

    For now you'll just have to clone this repo

    Usage

    Start the pigpio daemon:

    $ sudo pigpiod
    

    In your program:

    1. require(...) the pi-fast-gpio library
    2. Create a new instance of the PiFastGpio class
    3. Call connect(...) to connect to the pigpiod daemon
    4. When connected, do what you please with the GPIOs on your Raspberry Pi
    5. Call close() when you're done and about to exit your program.

    Examples

    There are two examples included, one that drives two servos, and one that uses PWM to change the brightness of two LEDs

    Before running any of the examples, make sure the pigpio daemon is running:

    $ sudo pigpiod
    

    Servos example

    Watch the servos example in action here: http://youtu.be/AnlUtAq5oAM

    Before running the example, please connect two servos to your Raspberry Pi. One on GPIO18 and one on GPIO23.

    Go to the examples/ directory and run the code:

    $ node js_servo.js
    

    Watch the servos turn!

    LED PWM example

    Watch the LED PWM example in action here: http://youtu.be/OW6yF4NuwLE

    Before running the example, please connect to LEDs to your Raspberry Pi with suitable resistors. Connect one LED to GPIO24 and one to GPIO25.

    Go to the examples/ directory and run the code:

    $ node js_pwm.js
    

    Watch the LEDs light up with different brightness!

    Pin Layout tables

    (Tables copied from r-pi-gpio's readme file)

    Raspberry Pi GPIO Pin Layout (Revision 1)

    Assignment Pin Pin Assignment
    3.3V 1 2 5V
    GPIO 0 (I2C0 SDA) 3 4 DNC
    GPIO 1 (I2C0 SCL) 5 6 GROUND
    GPIO 4 7 8 GPIO 14 (UART TXD)
    DNC 9 10 GPIO 15 (UART RXD)
    GPIO 17 11 12 GPIO 18
    GPIO 21 13 14 DNC
    GPIO 22 15 16 GPIO 23
    DNC 17 18 GPIO 24
    GPIO 10 (SP10 MOSI) 19 20 DNC
    GPIO 9 (SP10 MISO) 21 22 GPIO 25
    GPIO 11 (SP10 SCLK) 23 24 GPIO 8 (SP10 CE0 N)
    DNC 25 26 GPIO 7 (SP10 CE1 N)

    Raspberry Pi GPIO Pin Layout (Revision 2)

    Assignment Pin Pin Assignment
    3.3V 1 2 5V
    GPIO 2 (I2C1 SDA) 3 4 5V
    GPIO 3 (I2C1 SCL) 5 6 GROUND
    GPIO 4 7 8 GPIO 14 (UART TXD)
    GROUND 9 10 GPIO 15 (UART RXD)
    GPIO 17 11 12 GPIO 18
    GPIO 27 13 14 GROUND
    GPIO 22 15 16 GPIO 23
    3.3V 17 18 GPIO 24
    GPIO 10 (SP10 MOSI) 19 20 GROUND
    GPIO 9 (SP10 MISO) 21 22 GPIO 25
    GPIO 11 (SP10 SCLK) 23 24 GPIO 8 (SP10 CE0 N)
    GROUND 25 26 GPIO 7 (SP10 CE1 N)

    Install

    npm i pi-fast-gpio

    DownloadsWeekly Downloads

    2

    Version

    0.1.0

    License

    ISC

    Last publish

    Collaborators

    • tobbe