簡介 原始碼及其來源

RPi.GPIO是Python的一個module( 模組 ), 樹莓派官方系統預設已經安裝, 仍在不斷更新中, 截至20160314, 最新版0.6.2, 適配了樹莓派3, 訪問 python主頁 . 
原始碼(也有教程的連結)公佈在Sourceforge上: 點 這裡 檢視原始碼.

簡介及注意事項:

A module to control Raspberry Pi GPIO channels.

This package provides a class to control the GPIO on a Raspberry Pi.

Note that this module is unsuitable for real-time or timing critical applications. This is because you can not predict when Python will be busy garbage collecting. It also runs under the Linux kernel which is not suitable for real time applications - it is multitasking O/S and another process may be given priority over the CPU, causing jitter in your program. If you are after true real-time performance and predictability, buy yourself an Arduino 

Note that the current release does not support SPI, I2C, hardware PWM or serial functionality on the RPi yet. This is planned for the near future - watch this space! One-wire functionality is also planned.

Although hardware PWM is not available yet, software PWM is available to use on all channels.

大致含義是: 這個包提供了操作樹莓派GPIO的一個類, 不是實時的, 不支援硬體的SPI,I2C,PWM等, 但軟體PWM可以在所有通道使用. 如果想要實時控制, 推薦Arduino. 
原始碼包中可以看到下列檔案: 

source資料夾中放置了 C語言操作底層暫存器以及外設封裝的原始碼, 感興趣的可以下載下來研究一下: 

test資料夾中放了test.py, 大量的測試程式碼, 很有參考價值: 

RPi Board Information and RPi.GPIO version

樹莓派官方系統預設已經安裝了Python和RPi.GPIO, 樹莓派終端輸入命令 python --version

To discover information about your RPi:

<code class="hljs avrasm has-numbering" style="display: block; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; background-image: initial; background-attachment: initial; background-origin: initial; background-clip: initial; background-color: transparent; color: inherit; box-sizing: border-box; font-family: 'Source Code Pro', monospace;font-size:undefined; white-space: pre; border-top-left-radius: 0px; border-top-right-radius: 0px; border-bottom-right-radius: 0px; border-bottom-left-radius: 0px; word-wrap: normal; background-position: initial initial; background-repeat: initial initial; ">GPIO<span class="hljs-preprocessor" style="color: rgb(68, 68, 68); box-sizing: border-box; ">.RPI</span>_INFO</code><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; background-color: rgb(238, 238, 238); top: 0px; left: 0px; margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 6px; padding-right: 0px; padding-bottom: 40px; padding-left: 0px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style-type: none; list-style-position: initial; list-style-image: initial; text-align: right; "><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">1</li></ul><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; background-color: rgb(238, 238, 238); top: 0px; left: 0px; margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 6px; padding-right: 0px; padding-bottom: 40px; padding-left: 0px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style-type: none; list-style-position: initial; list-style-image: initial; text-align: right; "><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">1</li></ul>

To discover the Raspberry Pi board revision:

<code class="hljs bash has-numbering" style="display: block; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; background-image: initial; background-attachment: initial; background-origin: initial; background-clip: initial; background-color: transparent; color: inherit; box-sizing: border-box; font-family: 'Source Code Pro', monospace;font-size:undefined; white-space: pre; border-top-left-radius: 0px; border-top-right-radius: 0px; border-bottom-right-radius: 0px; border-bottom-left-radius: 0px; word-wrap: normal; background-position: initial initial; background-repeat: initial initial; ">GPIO.RPI_INFO[<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box; ">'P1_REVISION'</span>]
GPIO.RPI_REVISION    <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box; ">#(deprecated 棄用)</span></code><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; background-color: rgb(238, 238, 238); top: 0px; left: 0px; margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 6px; padding-right: 0px; padding-bottom: 40px; padding-left: 0px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style-type: none; list-style-position: initial; list-style-image: initial; text-align: right; "><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">1</li><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">2</li></ul><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; background-color: rgb(238, 238, 238); top: 0px; left: 0px; margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 6px; padding-right: 0px; padding-bottom: 40px; padding-left: 0px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style-type: none; list-style-position: initial; list-style-image: initial; text-align: right; "><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">1</li><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">2</li></ul>

To discover the version of RPi.GPIO:

<code class="hljs avrasm has-numbering" style="display: block; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; background-image: initial; background-attachment: initial; background-origin: initial; background-clip: initial; background-color: transparent; color: inherit; box-sizing: border-box; font-family: 'Source Code Pro', monospace;font-size:undefined; white-space: pre; border-top-left-radius: 0px; border-top-right-radius: 0px; border-bottom-right-radius: 0px; border-bottom-left-radius: 0px; word-wrap: normal; background-position: initial initial; background-repeat: initial initial; ">GPIO<span class="hljs-preprocessor" style="color: rgb(68, 68, 68); box-sizing: border-box; ">.VERSION</span></code><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; background-color: rgb(238, 238, 238); top: 0px; left: 0px; margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 6px; padding-right: 0px; padding-bottom: 40px; padding-left: 0px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style-type: none; list-style-position: initial; list-style-image: initial; text-align: right; "><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">1</li></ul><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; background-color: rgb(238, 238, 238); top: 0px; left: 0px; margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 6px; padding-right: 0px; padding-bottom: 40px; padding-left: 0px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style-type: none; list-style-position: initial; list-style-image: initial; text-align: right; "><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">1</li></ul>

RPi.GPIO使用說明

像學一門語言第一個程式是”Hello World”一樣, 搞硬體的第一個任務是 點燈(Blink). 先來看下點燈的程式吧:

<code class="hljs python has-numbering" style="display: block; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; background-image: initial; background-attachment: initial; background-origin: initial; background-clip: initial; background-color: transparent; color: inherit; box-sizing: border-box; font-family: 'Source Code Pro', monospace;font-size:undefined; white-space: pre; border-top-left-radius: 0px; border-top-right-radius: 0px; border-bottom-right-radius: 0px; border-bottom-left-radius: 0px; word-wrap: normal; background-position: initial initial; background-repeat: initial initial; "><span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box; ">#!/usr/bin/python</span>
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box; ">import</span> RPi.GPIO <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box; ">as</span> GPIO
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box; ">import</span> sys
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box; ">import</span> time
LED = <span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box; ">21</span>
<span class="hljs-function" style="box-sizing: border-box; "><span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box; ">def</span> <span class="hljs-title" style="box-sizing: border-box; ">main</span><span class="hljs-params" style="color: rgb(102, 0, 102); box-sizing: border-box; ">()</span>:</span>
    GPIO.setwarnings(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box; ">False</span>)
    GPIO.setmode(GPIO.BCM)
    GPIO.setup(LED,GPIO.OUT)
    <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box; ">while</span> (<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box; ">True</span>):
        GPIO.output(LED,<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box; ">True</span>)
        time.sleep(<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box; ">0.5</span>)
        GPIO.output(LED,<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box; ">False</span>)        
        time.sleep(<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box; ">0.5</span>)
main()</code><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; background-color: rgb(238, 238, 238); top: 0px; left: 0px; margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 6px; padding-right: 0px; padding-bottom: 40px; padding-left: 0px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style-type: none; list-style-position: initial; list-style-image: initial; text-align: right; "><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">1</li><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">2</li><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">3</li><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">4</li><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">5</li><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">6</li><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">7</li><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">8</li><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">9</li><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">10</li><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">11</li><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">12</li><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">13</li><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">14</li><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">15</li></ul><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; background-color: rgb(238, 238, 238); top: 0px; left: 0px; margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 6px; padding-right: 0px; padding-bottom: 40px; padding-left: 0px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style-type: none; list-style-position: initial; list-style-image: initial; text-align: right; "><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">1</li><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">2</li><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">3</li><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">4</li><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">5</li><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">6</li><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">7</li><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">8</li><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">9</li><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">10</li><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">11</li><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">12</li><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">13</li><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">14</li><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">15</li></ul>

LED接在BCM編號方式下的21引腳, 每隔0.5s亮一次, time.sleep(), 延時秒數. 類似Arduino中的delay(), 當然,後者是延時的ms數.

具體每句話的意思, 往下面看:

Importing the module ( 匯入模組 )

To import the RPi.GPIO module(匯入RPi.GPIO模組):

<code class="hljs haskell has-numbering" style="display: block; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; background-image: initial; background-attachment: initial; background-origin: initial; background-clip: initial; background-color: transparent; color: inherit; box-sizing: border-box; font-family: 'Source Code Pro', monospace;font-size:undefined; white-space: pre; border-top-left-radius: 0px; border-top-right-radius: 0px; border-bottom-right-radius: 0px; border-bottom-left-radius: 0px; word-wrap: normal; background-position: initial initial; background-repeat: initial initial; "><span class="hljs-import" style="box-sizing: border-box; "><span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box; ">import</span> RPi.GPIO <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box; ">as</span> GPIO</span></code><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; background-color: rgb(238, 238, 238); top: 0px; left: 0px; margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 6px; padding-right: 0px; padding-bottom: 40px; padding-left: 0px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style-type: none; list-style-position: initial; list-style-image: initial; text-align: right; "><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">1</li></ul><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; background-color: rgb(238, 238, 238); top: 0px; left: 0px; margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 6px; padding-right: 0px; padding-bottom: 40px; padding-left: 0px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style-type: none; list-style-position: initial; list-style-image: initial; text-align: right; "><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">1</li></ul>

To import the module and check to see if it is successful( 判斷檢查匯入模組是否成功, 可能需要超級使用者許可權執行: sudo python xx.py ):

<code class="hljs python has-numbering" style="display: block; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; background-image: initial; background-attachment: initial; background-origin: initial; background-clip: initial; background-color: transparent; color: inherit; box-sizing: border-box; font-family: 'Source Code Pro', monospace;font-size:undefined; white-space: pre; border-top-left-radius: 0px; border-top-right-radius: 0px; border-bottom-right-radius: 0px; border-bottom-left-radius: 0px; word-wrap: normal; background-position: initial initial; background-repeat: initial initial; "><span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box; ">try</span>:
    <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box; ">import</span> RPi.GPIO <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box; ">as</span> GPIO
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box; ">except</span> RuntimeError:
    print(<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box; ">"Error importing RPi.GPIO!  This is probably because you need superuser privileges.  You can achieve this by using 'sudo' to run your script"</span>)</code><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; background-color: rgb(238, 238, 238); top: 0px; left: 0px; margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 6px; padding-right: 0px; padding-bottom: 40px; padding-left: 0px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style-type: none; list-style-position: initial; list-style-image: initial; text-align: right; "><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">1</li><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">2</li><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">3</li><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">4</li></ul><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; background-color: rgb(238, 238, 238); top: 0px; left: 0px; margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 6px; padding-right: 0px; padding-bottom: 40px; padding-left: 0px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style-type: none; list-style-position: initial; list-style-image: initial; text-align: right; "><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">1</li><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">2</li><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">3</li><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">4</li></ul>

Pin numbering ( 引腳編號 )

There are two ways of numbering the IO pins on a Raspberry Pi within RPi.GPIO. The first is using the BOARD numbering system. This refers to the pin numbers on the P1 header of the Raspberry Pi board. The advantage of using this numbering system is that your hardware will always work, regardless of the board revision of the RPi. You will not need to rewire your connector or change your code.

The second numbering system is the BCM numbers. This is a lower level way of working - it refers to the channel numbers on the Broadcom SOC. You have to always work with a diagram of which channel number goes to which pin on the RPi board. Your script could break between revisions of Raspberry Pi boards.

大致含義: 樹莓派引腳有BOARD和BCM兩種編號方式( 使用python時? 似乎使用C還有一種wringPi編號方式 ), BOARD具有很好的適用性( 不用看介面圖,數引腳1~40就可以接線 ), 不論樹莓派1 2 3, 都不用修改程式碼, 吼啊! BCM編號方式換個版本再接線時數引腳是不行的, 需要看下下面的介面圖…不難看出推薦用BOARD編號方式. 但很多程式中使用BCM方式. 
下面給出一張樹莓派2B的硬體介面圖( 來源找不到了,侵刪 ): 

圖中的GPIOxx的方框即是BCM編碼方式, 直接寫數字的深灰框是BOARD編碼方式, 如BCM編碼方式的 GPIO02 對應BOARD編碼方式的 3.

只需要使用BCM編號方式時, 用下面這兩張好了, 不眼花: 

終端檢視BCM編號的方式: 

To specify which you are using using (mandatory)(確認使用的引腳編號方式):

<code class="hljs avrasm has-numbering" style="display: block; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; background-image: initial; background-attachment: initial; background-origin: initial; background-clip: initial; background-color: transparent; color: inherit; box-sizing: border-box; font-family: 'Source Code Pro', monospace;font-size:undefined; white-space: pre; border-top-left-radius: 0px; border-top-right-radius: 0px; border-bottom-right-radius: 0px; border-bottom-left-radius: 0px; word-wrap: normal; background-position: initial initial; background-repeat: initial initial; ">GPIO<span class="hljs-preprocessor" style="color: rgb(68, 68, 68); box-sizing: border-box; ">.setmode</span>(GPIO<span class="hljs-preprocessor" style="color: rgb(68, 68, 68); box-sizing: border-box; ">.BOARD</span>)
  <span class="hljs-preprocessor" style="color: rgb(68, 68, 68); box-sizing: border-box; "># or</span>
GPIO<span class="hljs-preprocessor" style="color: rgb(68, 68, 68); box-sizing: border-box; ">.setmode</span>(GPIO<span class="hljs-preprocessor" style="color: rgb(68, 68, 68); box-sizing: border-box; ">.BCM</span>)</code><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; background-color: rgb(238, 238, 238); top: 0px; left: 0px; margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 6px; padding-right: 0px; padding-bottom: 40px; padding-left: 0px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style-type: none; list-style-position: initial; list-style-image: initial; text-align: right; "><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">1</li><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">2</li><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">3</li></ul><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; background-color: rgb(238, 238, 238); top: 0px; left: 0px; margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 6px; padding-right: 0px; padding-bottom: 40px; padding-left: 0px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style-type: none; list-style-position: initial; list-style-image: initial; text-align: right; "><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">1</li><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">2</li><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">3</li></ul>

To detect which pin numbering system has been set (for example, by another Python module)(檢測使用的是哪種編號方式):

<code class="hljs mizar has-numbering" style="display: block; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; background-image: initial; background-attachment: initial; background-origin: initial; background-clip: initial; background-color: transparent; color: inherit; box-sizing: border-box; font-family: 'Source Code Pro', monospace;font-size:undefined; white-space: pre; border-top-left-radius: 0px; border-top-right-radius: 0px; border-bottom-right-radius: 0px; border-bottom-left-radius: 0px; word-wrap: normal; background-position: initial initial; background-repeat: initial initial; ">#The <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box; ">mode</span> will <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box; ">be</span> GPIO.BOARD, GPIO.BCM <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box; ">or</span> None
<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box; ">mode</span> = GPIO.getmode()</code><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; background-color: rgb(238, 238, 238); top: 0px; left: 0px; margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 6px; padding-right: 0px; padding-bottom: 40px; padding-left: 0px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style-type: none; list-style-position: initial; list-style-image: initial; text-align: right; "><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">1</li><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">2</li></ul><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; background-color: rgb(238, 238, 238); top: 0px; left: 0px; margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 6px; padding-right: 0px; padding-bottom: 40px; padding-left: 0px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style-type: none; list-style-position: initial; list-style-image: initial; text-align: right; "><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">1</li><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">2</li></ul>

Warning(警告)

It is possible that you have more than one script/circuit on the GPIO of your Raspberry Pi. As a result of this, if RPi.GPIO detects that a pin has been configured to something other than the default (input), you get a warning when you try to configure a script. To disable these warnings:

樹莓派可能不止有一個指令碼/電路在操縱GPIO, 如果樹莓派檢測到引腳不是預設的輸入狀態, 會給出警告, 可以用一行程式碼避免警告:

<code class="hljs mathematica has-numbering" style="display: block; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; background-image: initial; background-attachment: initial; background-origin: initial; background-clip: initial; background-color: transparent; color: inherit; box-sizing: border-box; font-family: 'Source Code Pro', monospace;font-size:undefined; white-space: pre; border-top-left-radius: 0px; border-top-right-radius: 0px; border-bottom-right-radius: 0px; border-bottom-left-radius: 0px; word-wrap: normal; background-position: initial initial; background-repeat: initial initial; ">GPIO.setwarnings(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box; ">False</span>)</code><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; background-color: rgb(238, 238, 238); top: 0px; left: 0px; margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 6px; padding-right: 0px; padding-bottom: 40px; padding-left: 0px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style-type: none; list-style-position: initial; list-style-image: initial; text-align: right; "><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">1</li></ul><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; background-color: rgb(238, 238, 238); top: 0px; left: 0px; margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 6px; padding-right: 0px; padding-bottom: 40px; padding-left: 0px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style-type: none; list-style-position: initial; list-style-image: initial; text-align: right; "><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">1</li></ul>

Setup up a channel(設定一個通道)

You need to set up every channel you are using as an input or an output. 
你需要設定用作輸入輸出的引腳. 
To configure a channel as an input( 通道設定為輸入 ) :

<code class="hljs avrasm has-numbering" style="display: block; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; background-image: initial; background-attachment: initial; background-origin: initial; background-clip: initial; background-color: transparent; color: inherit; box-sizing: border-box; font-family: 'Source Code Pro', monospace;font-size:undefined; white-space: pre; border-top-left-radius: 0px; border-top-right-radius: 0px; border-bottom-right-radius: 0px; border-bottom-left-radius: 0px; word-wrap: normal; background-position: initial initial; background-repeat: initial initial; ">GPIO<span class="hljs-preprocessor" style="color: rgb(68, 68, 68); box-sizing: border-box; ">.setup</span>(channel, GPIO<span class="hljs-preprocessor" style="color: rgb(68, 68, 68); box-sizing: border-box; ">.IN</span>)</code><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; background-color: rgb(238, 238, 238); top: 0px; left: 0px; margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 6px; padding-right: 0px; padding-bottom: 40px; padding-left: 0px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style-type: none; list-style-position: initial; list-style-image: initial; text-align: right; "><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">1</li></ul><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; background-color: rgb(238, 238, 238); top: 0px; left: 0px; margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 6px; padding-right: 0px; padding-bottom: 40px; padding-left: 0px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style-type: none; list-style-position: initial; list-style-image: initial; text-align: right; "><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">1</li></ul>

(where channel is the channel number based on the numbering system you have specified (BOARD or BCM))( channel引數為BOARD或BCM的引腳編號 ).

To read the value of a GPIO pin( 讀輸入引腳的值 ):

<code class="hljs lasso has-numbering" style="display: block; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; background-image: initial; background-attachment: initial; background-origin: initial; background-clip: initial; background-color: transparent; color: inherit; box-sizing: border-box; font-family: 'Source Code Pro', monospace;font-size:undefined; white-space: pre; border-top-left-radius: 0px; border-top-right-radius: 0px; border-bottom-right-radius: 0px; border-bottom-left-radius: 0px; word-wrap: normal; background-position: initial initial; background-repeat: initial initial; "><span class="hljs-variable" style="color: rgb(102, 0, 102); box-sizing: border-box; ">#This</span> will <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box; ">return</span> either <span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box; ">0</span> <span class="hljs-subst" style="color: rgb(0, 0, 0); box-sizing: border-box; ">/</span> GPIO<span class="hljs-built_in" style="color: rgb(102, 0, 102); box-sizing: border-box; ">.</span>LOW <span class="hljs-subst" style="color: rgb(0, 0, 0); box-sizing: border-box; ">/</span> <span class="hljs-literal" style="color: rgb(0, 102, 102); box-sizing: border-box; ">False</span> <span class="hljs-literal" style="color: rgb(0, 102, 102); box-sizing: border-box; ">or</span> <span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box; ">1</span> <span class="hljs-subst" style="color: rgb(0, 0, 0); box-sizing: border-box; ">/</span> GPIO<span class="hljs-built_in" style="color: rgb(102, 0, 102); box-sizing: border-box; ">.</span>HIGH <span class="hljs-subst" style="color: rgb(0, 0, 0); box-sizing: border-box; ">/</span> <span class="hljs-literal" style="color: rgb(0, 102, 102); box-sizing: border-box; ">True</span><span class="hljs-built_in" style="color: rgb(102, 0, 102); box-sizing: border-box; ">.</span>
GPIO<span class="hljs-built_in" style="color: rgb(102, 0, 102); box-sizing: border-box; ">.</span>input(channel) </code><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; background-color: rgb(238, 238, 238); top: 0px; left: 0px; margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 6px; padding-right: 0px; padding-bottom: 40px; padding-left: 0px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style-type: none; list-style-position: initial; list-style-image: initial; text-align: right; "><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">1</li><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">2</li></ul><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; background-color: rgb(238, 238, 238); top: 0px; left: 0px; margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 6px; padding-right: 0px; padding-bottom: 40px; padding-left: 0px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style-type: none; list-style-position: initial; list-style-image: initial; text-align: right; "><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">1</li><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">2</li></ul>

To set up a channel as an output( 設定為輸出 ):

<code class="hljs avrasm has-numbering" style="display: block; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; background-image: initial; background-attachment: initial; background-origin: initial; background-clip: initial; background-color: transparent; color: inherit; box-sizing: border-box; font-family: 'Source Code Pro', monospace;font-size:undefined; white-space: pre; border-top-left-radius: 0px; border-top-right-radius: 0px; border-bottom-right-radius: 0px; border-bottom-left-radius: 0px; word-wrap: normal; background-position: initial initial; background-repeat: initial initial; ">GPIO<span class="hljs-preprocessor" style="color: rgb(68, 68, 68); box-sizing: border-box; ">.setup</span>(channel, GPIO<span class="hljs-preprocessor" style="color: rgb(68, 68, 68); box-sizing: border-box; ">.OUT</span>)</code><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; background-color: rgb(238, 238, 238); top: 0px; left: 0px; margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 6px; padding-right: 0px; padding-bottom: 40px; padding-left: 0px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style-type: none; list-style-position: initial; list-style-image: initial; text-align: right; "><li style="box-sizing: border-box; padding-top: 0px; padding-right: 5px; padding-bottom: 0px; padding-left: 5px; ">1</li></ul><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; background-color: rgb(238, 238, 238); top: 0px; left: 0px; margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 6px; padding-right: 0px; padding-bottom: 40px; padding-left: 0px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style-type: none; list-sty