Install WiringPi and controlling raspberrypi gpio pins with php

WiringPi is a GPIO access library written in C for the BCM2835 used in the Raspberry Pi.
How to download wiring pi?
If you do not have GIT installed, then under any of the Debian releases (e.g. Raspbian), you can install it with:

sudo apt-get install git-core

To obtain WiringPi using GIT

git clone git://git.drogon.net/wiringPi

If you have already used the clone operation for the first time, then

cd wiringPi
git pull origin

To build/install there is a new simplified script:

cd wiringPi
./build

Get version info of wiring pi

gpio -v

 
Before you get started you should now how & what pins do. Read details on “Special Pin Functions”
If you are new to raspberry Pi. You can follow the guide “How to blink a led“.
 
Read value of wiring pi socket number.

gpio read 1

Read value of raspberry pi socket number.

gpio -g read 1

Change mode of a pin to “up”

gpio -g mode 18 up

Change mode of a pin to “down”

gpio -g mode 18 down

 
Write value of wiring pi socket number.

gpio write 29 1

Get the detailed stats of gpio pins

gpio readall

According to it, configure GPIO18 (WiringPi Pin 1) in HW PWM Mode using the command shell:

gpio mode 1 pwm

 
Write a value to the PWM module (from 1 to 1023):

gpio pwm 1 500

 
To remove the configuration of the pin, use:

gpio unexport 1

 
To remove all configurations:

gpio unexportall

 
How to run gpio commands via php

<?php
system ( "gpio mode 0 out" );
system ( "gpio write 0 1" );
exec ( "gpio read 0", $status );
print_r ( $status );
?>

 
You can see the Wiring Pi Chart
 

wiringPi Pin	BCM GPIO	Name	Header	Name	BCM GPIO	wiringPi Pin
—	—	3.3v	1 | 2	5v	—	—
8	R1:0/R2:2	SDA	3 | 4	5v	—	—
9	R1:1/R2:3	SCL	5 | 6	0v	—	—
7	4	GPIO7	7 | 8	TxD	14	15
—	—	0v	9 | 10	RxD	15	16
0	17	GPIO0	11 | 12	GPIO1	18	1
2	R1:21/R2:27	GPIO2	13 | 14	0v	—	—
3	22	GPIO3	15 | 16	GPIO4	23	4
—	—	3.3v	17 | 18	GPIO5	24	5
12	10	MOSI	19 | 20	0v	—	—
13	9	MISO	21 | 22	GPIO6	25	6
14	11	SCLK	23 | 24	CE0	8	10
—	—	0v	25 | 26	CE1	7	11
wiringPi Pin	BCM GPIO	Name	Header	Name	BCM GPIO	wiringPi Pin

 

• Board Revisions: Please note the differences between board revisions 1 and 2 (R1 and R2 above)

P5: The auxiliary GPIO connector present on Rev. 2 boards only:
 

wiringPi Pin	BCM GPIO	Name	Header	Name	BCM GPIO	wiringPi Pin
—	—	5v	1 | 2	3.3v	—	—
17	28	GPIO8	3 | 4	GPIO9	29	18
19	30	GPIO10	5 | 6	GPIO11	31	20
—	—	0v	7 | 8	0v	—	—
wiringPi Pin	BCM GPIO	Name	Header	Name	BCM GPIO	wiringPi Pin