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Beaglebone - Basic Informations

 

In this page, I will try to provide various information that is required for you to program on Beaglebone board. More importantly I will try to let you know how to find those information that is specific to your board. One of the difficulties that I noticed when I first playing with this board was that there is not much of the information like Arduino. Even more seious problem was .. even though I found something that looks helpful, it didn't work in most case when I just blindly copy and past those materials. As I learn more about the board and Linux on the board later, I learned that there are many variations depending on the type of the board (e.g, Beaglebone Black / White / Green) and Linux Kernel versions. Therefore, if you just blindly copy and past the information from this page, it may not work with your own board. So I suggest you to read my description in this page and understand how I find these information and apply the same trick with your board.

 

 

Linux Kernel and Distribution Information

 

 

 

    root@beaglebone:~# uname -a

    Linux beaglebone 3.8.13-bone71.1 #1 SMP Wed May 20 20:13:27 PDT 2015 armv7l GNU/Linux

     

    root@beaglebone:~# lsb_release -a

    No LSB modules are available.

    Distributor ID: Debian

    Description:    Debian GNU/Linux 7.8 (wheezy)

    Release:        7.8

    Codename:       wheezy

 

 

CPU Information

 

    root@beaglebone:~# lscpu

    Architecture:          armv7l

    Byte Order:            Little Endian

    CPU(s):                1

    On-line CPU(s) list:   0

    Thread(s) per core:    1

    Core(s) per socket:    1

    Socket(s):             1

 

 

Storage (Memory) information

 

    root@beaglebone:~# lsblk

    NAME         MAJ:MIN RM   SIZE RO TYPE MOUNTPOINT

    mmcblk0boot0 179:8    0     2M  1 disk

    mmcblk0boot1 179:16   0     2M  1 disk

    mmcblk0      179:0    0   3.6G  0 disk

    |-mmcblk0p1  179:1    0    96M  0 part /media/BEAGLEBONE

    `-mmcblk0p2  179:2    0   3.5G  0 part /

 

 

Pin Description

 

Pin mapping and the functionality of each pin may be a little different from the type of the board. So it is important to get the right document specific for your board. So I would not write down all the pin mapping document here. I will just let you know where you can find the document for the board that you are using.  It is simple, just broswer to 192.168.7.2 and scroll down the page until you find something like this. Since each single pin can have multiple different functionalities, you will see multiple different pin mappings in the page.

 

 

Even though the Pin Mapping diagram shown above is from the document installed on my Beaglebone Green board, based on some of the test that I did it seems that the correct ping mapping is as shown below. I would suggest you to check on your own for the board that you are using. (The way that I confirmed is to export GPIO 60, GPIO 48 and GPIO 66 as described in Export GPIO pins section. So, I think it is highly likely that following diagram is correct one. You may try the same procedure with the board that you are using)

 

 

If you reach a certain level of experience in microcontroller and want to get very detailed information, you may refer to following documentation.

 

Even though you are able to find the detailed information on the technical reference, it is not easy to find the exact information that is necessary for programming. I think the contents in bone.js file would give you better / handy information for programming.

 

Depending on Linux kernal and distribution installed on the board, this file may located in different places. So you may have difficulties to finding the location of the file. In this case, you may do similar tricks that I often use.. i.e, using following two steps.

 

root@beaglebone:cd / <== go to root folder

root@beaglebone:ls -R | grep "bone.js" <== find the location of bone.js

 

Once I find the location of the bone.js, I moved to the location and print out the contents as follows

 

root@beaglebone:cd /usr/local/lib/node_modules/bonescript

 

root@beaglebone:/usr/local/lib/node_modules/bonescript# cat < bone.js

 

if(typeof exports === 'undefined') exports = {};

 

var pinIndex = [

    {

        "name": "USR0",

        "gpio": 53,

        "led": "usr0",

        "mux": "gpmc_a5",

        "key": "USR0",

        "muxRegOffset": "0x054",

        "options": [

            "gpmc_a5",

            "gmii2_txd0",

            "rgmii2_td0",

            "rmii2_txd0",

            "gpmc_a21",

            "pr1_mii1_rxd3",

            "eqep1b_in",

            "gpio1_21"

        ]

    },

    {

        "name": "USR1",

        "gpio": 54,

        "led": "usr1",

        "mux": "gpmc_a6",

        "key": "USR1",

        "muxRegOffset": "0x058",

        "options": [

            "gpmc_a6",

            "gmii2_txclk",

            "rgmii2_tclk",

            "mmc2_dat4",

            "gpmc_a22",

            "pr1_mii1_rxd2",

            "eqep1_index",

            "gpio1_22"

        ]

    },

    {

        "name": "USR2",

        "gpio": 55,

        "led": "usr2",

        "mux": "gpmc_a7",

        "key": "USR2",

        "muxRegOffset": "0x05c",

        "options": [

            "gpmc_a7",

            "gmii2_rxclk",

            "rgmii2_rclk",

            "mmc2_dat5",

            "gpmc_a23",

            "pr1_mii1_rxd1",

            "eqep1_strobe",

            "gpio1_23"

        ]

    },

    {

        "name": "USR3",

        "gpio": 56,

        "led": "usr3",

        "mux": "gpmc_a8",

        "key": "USR3",

        "muxRegOffset": "0x060",

        "options": [

            "gpmc_a8",

            "gmii2_rxd3",

            "rgmii2_rd3",

            "mmc2_dat6",

            "gpmc_a24",

            "pr1_mii1_rxd0",

            "mcasp0_aclkx",

            "gpio1_24"

        ]

    },

    {

        "name": "DGND",

        "key": "P8_1"

    },

    {

        "name": "DGND",

        "key": "P8_2"

    },

    {

        "name": "GPIO1_6",

        "gpio": 38,

        "mux": "gpmc_ad6",

        "eeprom": 26,

        "key": "P8_3",

        "muxRegOffset": "0x018",

        "options": [

            "gpmc_ad6",

            "mmc1_dat6",

            "NA",

            "NA",

            "NA",

            "NA",

            "NA",

            "gpio1_6"

        ]

    },

    {

        "name": "GPIO1_7",

        "gpio": 39,

        "mux": "gpmc_ad7",

        "eeprom": 27,

        "key": "P8_4",

        "muxRegOffset": "0x01c",

        "options": [

            "gpmc_ad7",

            "mmc1_dat7",

            "NA",

            "NA",

            "NA",

            "NA",

            "NA",

            "gpio1_7"

        ]

    },

    {

        "name": "GPIO1_2",

        "gpio": 34,

        "mux": "gpmc_ad2",

        "eeprom": 22,

        "key": "P8_5",

        "muxRegOffset": "0x008",

        "options": [

            "gpmc_ad2",

            "mmc1_dat2",

            "NA",

            "NA",

            "NA",

            "NA",

            "NA",

            "gpio1_2"

        ]

    },

    {

        "name": "GPIO1_3",

        "gpio": 35,

        "mux": "gpmc_ad3",

        "eeprom": 23,

        "key": "P8_6",

        "muxRegOffset": "0x00c",

        "options": [

            "gpmc_ad3",

            "mmc1_dat3",

            "NA",

            "NA",

            "NA",

            "NA",

            "NA",

            "gpio1_3"

        ]

    },

    {

        "name": "TIMER4",

        "gpio": 66,

        "mux": "gpmc_advn_ale",

        "eeprom": 41,

        "key": "P8_7",

        "muxRegOffset": "0x090",

        "options": [

            "gpmc_advn_ale",

            "NA",

            "NA",

            "NA",

            "NA",

            "NA",

            "NA",

            "mmc1_sdcd"

        ]

    },

    {

        "name": "TIMER7",

        "gpio": 67,

        "mux": "gpmc_oen_ren",

        "eeprom": 44,

        "key": "P8_8",

        "muxRegOffset": "0x094",

        "options": [

            "gpmc_oen_ren",

            "NA",

            "NA",

            "NA",

            "NA",

            "NA",

            "NA",

            "gpio2_3"

        ]

    },

    {

        "name": "TIMER5",

        "gpio": 69,

        "mux": "gpmc_ben0_cle",

        "eeprom": 42,

        "key": "P8_9",

        "muxRegOffset": "0x09c",

        "options": [

            "gpmc_ben0_cle",

            "NA",

            "NA",

            "NA",

            "NA",

            "NA",

            "NA",

            "gpio2_5"

        ]

    },

    {

        "name": "TIMER6",

        "gpio": 68,

        "mux": "gpmc_wen",

        "eeprom": 43,

        "key": "P8_10",

        "muxRegOffset": "0x098",

        "options": [

            "gpmc_wen",

            "NA",

            "NA",

            "NA",

            "NA",

            "NA",

            "NA",

            "gpio2_4"

        ]

    },

    {

        "name": "GPIO1_13",

        "gpio": 45,

        "mux": "gpmc_ad13",

        "eeprom": 29,

        "key": "P8_11",

        "muxRegOffset": "0x034",

        "options": [

            "gpmc_ad13",

            "lcd_data18",

            "mmc1_dat5",

            "mmc2_dat1",

            "eqep2B_in",

            "pr1_mii0_txd",

            "pr1_pru0_pru_r30_15",

            "gpio1_13"

        ]

    },

    {

        "name": "GPIO1_12",

        "gpio": 44,

        "mux": "gpmc_ad12",

        "eeprom": 28,

        "key": "P8_12",

        "muxRegOffset": "0x030",

        "options": [

            "gpmc_ad12",

            "lcd_data19",

            "mmc1_dat4",

            "mmc2_dat0",

            "eqep2a_in",

            "pr1_mii0_txd2",

            "pr1_pru0_pru_r30_14",

            "gpio1_12"

        ]

    },

    {

        "name": "EHRPWM2B",

        "gpio": 23,

        "mux": "gpmc_ad9",

        "eeprom": 15,

        "pwm": {

            "module": "ehrpwm2",

            "index": 1,

            "muxmode": 4,

            "path": "ehrpwm.2:1",

            "name": "EHRPWM2B"

        },

        "key": "P8_13",

        "muxRegOffset": "0x024",

        "options": [

            "gpmc_ad9",

            "lcd_data22",

            "mmc1_dat1",

            "mmc2_dat5",

            "ehrpwm2B",

            "pr1_mii0_col",

            "NA",

            "gpio0_23"

        ]

    },

    {

        "name": "GPIO0_26",

        "gpio": 26,

        "mux": "gpmc_ad10",

        "eeprom": 16,

        "key": "P8_14",

        "muxRegOffset": "0x028",

        "options": [

            "gpmc_ad10",

            "lcd_data21",

            "mmc1_dat2",

            "mmc2_dat6",

            "ehrpwm2_tripzone_input",

            "pr1_mii0_txen",

            "NA",

            "gpio0_26"

        ]

    },

    {

        "name": "GPIO1_15",

        "gpio": 47,

        "mux": "gpmc_ad15",

        "eeprom": 31,

        "key": "P8_15",

        "muxRegOffset": "0x03c",

        "options": [

            "gpmc_ad15",

            "lcd_data16",

            "mmc1_dat7",

            "mmc2_dat3",

            "eqep2_strobe",

            "pr1_ecap0_ecap_capin_apwm_o",

            "pr1_pru0_pru_r31_15",

            "gpio1_15"

        ]

    },

    {

        "name": "GPIO1_14",

        "gpio": 46,

        "mux": "gpmc_ad14",

        "eeprom": 30,

        "key": "P8_16",

        "muxRegOffset": "0x038",

        "options": [

            "gpmc_ad14",

            "lcd_data17",

            "mmc1_dat6",

            "mmc2_dat2",

            "eqep2_index",

            "pr1_mii0_txd0",

            "pr1_pru0_pru_r31_14",

            "gpio1_14"

        ]

    },

    {

        "name": "GPIO0_27",

        "gpio": 27,

        "mux": "gpmc_ad11",

        "eeprom": 17,

        "key": "P8_17",

        "muxRegOffset": "0x02c",

        "options": [

            "gpmc_ad11",

            "lcd_data20",

            "mmc1_dat3",

            "mmc2_dat7",

            "ehrpwm0_synco",

            "pr1_mii0_txd3",

            "NA",

            "gpio0_27"

        ]

    },

    {

        "name": "GPIO2_1",

        "gpio": 65,

        "mux": "gpmc_clk",

        "eeprom": 40,

        "key": "P8_18",

        "muxRegOffset": "0x08c",

        "options": [

            "gpmc_clk",

            "lcd_memory_clk_mux",

            "NA",

            "mmc2_clk",

            "NA",

            "NA",

            "mcasp0_fsr",

            "gpio2_1"

        ]

    },

    {

        "name": "EHRPWM2A",

        "gpio": 22,

        "mux": "gpmc_ad8",

        "eeprom": 14,

        "pwm": {

            "module": "ehrpwm2",

            "index": 0,

            "muxmode": 4,

            "path": "ehrpwm.2:0",

            "name": "EHRPWM2A"

        },

        "key": "P8_19",

        "muxRegOffset": "0x020",

        "options": [

            "gpmc_ad8",

            "lcd_data23",

            "mmc1_dat0",

            "mmc2_dat4",

            "ehrpwm2A",

            "pr1_mii_mt0_clk",

            "NA",

            "gpio0_22"

        ]

    },

    {

        "name": "GPIO1_31",

        "gpio": 63,

        "mux": "gpmc_csn2",

        "eeprom": 39,

        "key": "P8_20",

        "muxRegOffset": "0x084",

        "options": [

            "gpmc_csn2",

            "gpmc_be1n",

            "mmc1_cmd",

            "pr1_edio_data_in7",

            "pr1_edio_data_out7",

            "pr1_pru1_pru_r30_13",

            "pr1_pru1_pru_r31_13",

            "gpio1_31"

        ]

    },

    {

        "name": "GPIO1_30",

        "gpio": 62,

        "mux": "gpmc_csn1",

        "eeprom": 38,

        "key": "P8_21",

        "muxRegOffset": "0x080",

        "options": [

            "gpmc_csn1",

            "gpmc_clk",

            "mmc1_clk",

            "pr1_edio_data_in6",

            "pr1_edio_data_out6",

            "pr1_pru1_pru_r30_12",

            "pr1_pru1_pru_r31_12",

            "gpio1_30"

        ]

    },

    {

        "name": "GPIO1_5",

        "gpio": 37,

        "mux": "gpmc_ad5",

        "eeprom": 25,

        "key": "P8_22",

        "muxRegOffset": "0x014",

        "options": [

            "gpmc_ad5",

            "mmc1_dat5",

            "NA",

            "NA",

            "NA",

            "NA",

            "NA",

            "gpio1_5"

        ]

    },

    {

        "name": "GPIO1_4",

        "gpio": 36,

        "mux": "gpmc_ad4",

        "eeprom": 24,

        "key": "P8_23",

        "muxRegOffset": "0x010",

        "options": [

            "gpmc_ad4",

            "mmc1_dat4",

            "NA",

            "NA",

            "NA",

            "NA",

            "NA",

            "gpio1_4"

        ]

    },

    {

        "name": "GPIO1_1",

        "gpio": 33,

        "mux": "gpmc_ad1",

        "eeprom": 21,

        "key": "P8_24",

        "muxRegOffset": "0x004",

        "options": [

            "gpmc_ad1",

            "mmc1_dat1",

            "NA",

            "NA",

            "NA",

            "NA",

            "NA",

            "gpio1_1"

        ]

    },

    {

        "name": "GPIO1_0",

        "gpio": 32,

        "mux": "gpmc_ad0",

        "eeprom": 20,

        "key": "P8_25",

        "muxRegOffset": "0x000",

        "options": [

            "gpmc_ad0",

            "mmc1_dat0",

            "NA",

            "NA",

            "NA",

            "NA",

            "NA",

            "gpio1_0"

        ]

    },

    {

        "name": "GPIO1_29",

        "gpio": 61,

        "mux": "gpmc_csn0",

        "eeprom": 37,

        "key": "P8_26",

        "muxRegOffset": "0x07c",

        "options": [

            "gpmc_csn0",

            "NA",

            "NA",

            "NA",

            "NA",

            "NA",

            "NA",

            "gpio1_29"

        ]

    },

    {

        "name": "GPIO2_22",

        "gpio": 86,

        "mux": "lcd_vsync",

        "eeprom": 57,

        "key": "P8_27",

        "muxRegOffset": "0x0e0",

        "options": [

            "lcd_vsync",

            "gpmc_a8",

            "NA",

            "pr1_edio_data_in2",

            "pr1_edio_data_out2",

            "pr1_pru1_pru_r30_8",

            "pr1_pru1_pru_r31_8",

            "gpio2_22"

        ]

    },

    {

        "name": "GPIO2_24",

        "gpio": 88,

        "mux": "lcd_pclk",

        "eeprom": 59,

        "key": "P8_28",

        "muxRegOffset": "0x0e8",

        "options": [

            "lcd_pclk",

            "gpmc_a10",

            "pr1_mii0_crs",

            "pr1_edio_data_in4",

            "pr1_edio_data_out4",

            "pr1_pru1_pru_r30_10",

            "pr1_pru1_pru_r31_10",

            "gpio2_24"

        ]

    },

    {

        "name": "GPIO2_23",

        "gpio": 87,

        "mux": "lcd_hsync",

        "eeprom": 58,

        "key": "P8_29",

        "muxRegOffset": "0x0e4",

        "options": [

            "lcd_hsync",

            "gpmc_a9",

            "NA",

            "pr1_edio_data_in3",

            "pr1_edio_data_out3",

            "pr1_pru1_pru_r30_9",

            "pr1_pru1_pru_r31_9",

            "gpio2_23"

        ]

    },

    {

        "name": "GPIO2_25",

        "gpio": 89,

        "mux": "lcd_ac_bias_en",

        "eeprom": 60,

        "key": "P8_30",

        "muxRegOffset": "0x0ec",

        "options": [

            "lcd_ac_bias_en",

            "gpmc_a11",

            "pr1_mii1_crs",

            "pr1_edio_data_in5",

            "pr1_edio_data_out5",

            "pr1_pru1_pru_r30_11",

            "pr1_pru1_pru_r31_11",

            "gpio2_25"

        ]

    },

    {

        "name": "UART5_CTSN",

        "gpio": 10,

        "mux": "lcd_data14",

        "eeprom": 7,

        "key": "P8_31",

        "muxRegOffset": "0x0d8",

        "options": [

            "lcd_data14",

            "gpmc_a18",

            "NA",

            "mcasp0_axr1",

            "NA",

            "NA",

            "NA",

            "gpio0_10"

        ]

    },

    {

        "name": "UART5_RTSN",

        "gpio": 11,

        "mux": "lcd_data15",

        "eeprom": 8,

        "key": "P8_32",

        "muxRegOffset": "0x0dc",

        "options": [

            "lcd_data15",

            "gpmc_a19",

            "NA",

            "mcasp0_ahclkx",

            "mcasp0_axr3",

            "NA",

            "NA",

            "gpio0_11"

        ]

    },

    {

        "name": "UART4_RTSN",

        "gpio": 9,

        "mux": "lcd_data13",

        "eeprom": 6,

        "key": "P8_33",

        "muxRegOffset": "0x0d4",

        "options": [

            "lcd_data13",

            "gpmc_a17",

            "NA",

            "mcasp0_fsr",

            "mcasp0_axr3",

            "NA",

            "NA",

            "gpio0_9"

        ]

    },

    {

        "name": "UART3_RTSN",

        "gpio": 81,

        "mux": "lcd_data11",

        "eeprom": 56,

        "pwm": {

            "module": "ehrpwm1",

            "index": 1,

            "muxmode": 2,

            "path": "ehrpwm.1:1",

            "name": "EHRPWM1B"

        },

        "key": "P8_34",

        "muxRegOffset": "0x0cc",

        "options": [

            "lcd_data11",

            "gpmc_a15",

            "NA",

            "mcasp0_ahclkr",

            "mcasp0_axr2",

            "NA",

            "NA",

            "gpio2_17"

        ]

    },

    {

        "name": "UART4_CTSN",

        "gpio": 8,

        "mux": "lcd_data12",

        "eeprom": 5,

        "key": "P8_35",

        "muxRegOffset": "0x0d0",

        "options": [

            "lcd_data12",

            "gpmc_a16",

            "NA",

            "mcasp0_aclkr",

            "mcasp0_axr2",

            "NA",

            "NA",

            "gpio0_8"

        ]

    },

    {

        "name": "UART3_CTSN",

        "gpio": 80,

        "mux": "lcd_data10",

        "eeprom": 55,

        "pwm": {

            "module": "ehrpwm1",

            "index": 0,

            "muxmode": 2,

            "path": "ehrpwm.1:0",

            "name": "EHRPWM1A"

        },

        "key": "P8_36",

        "muxRegOffset": "0x0c8",

        "options": [

            "lcd_data10",

            "gpmc_a14",

            "ehrpwm1A",

            "mcasp0_axr0",

            "mcasp0_axr0",

            "pr1_mii0_rxd1",

            "uart3_ctsn",

            "gpio2_16"

        ]

    },

    {

        "name": "UART5_TXD",

        "gpio": 78,

        "mux": "lcd_data8",

        "eeprom": 53,

        "key": "P8_37",

        "muxRegOffset": "0x0c0",

        "options": [

            "lcd_data8",

            "gpmc_a12",

            "NA",

            "mcasp0_aclkx",

            "NA",

            "NA",

            "uart2_ctsn",

            "gpio2_14"

        ]

    },

    {

        "name": "UART5_RXD",

        "gpio": 79,

        "mux": "lcd_data9",

        "eeprom": 54,

        "key": "P8_38",

        "muxRegOffset": "0x0c4",

        "options": [

            "lcd_data9",

            "gpmc_a13",

            "NA",

            "mcasp0_fsx",

            "NA",

            "NA",

            "uart2_rtsn",

            "gpio2_15"

        ]

    },

    {

        "name": "GPIO2_12",

        "gpio": 76,

        "mux": "lcd_data6",

        "eeprom": 51,

        "key": "P8_39",

        "muxRegOffset": "0x0b8",

        "options": [

            "lcd_data6",

            "gpmc_a6",

            "pr1_edio_data_in6",

            "eqep2_index",

            "pr1_edio_data_out6",

            "pr1_pru1_pru_r30_6",

            "pr1_pru1_pru_r31_6",

            "gpio2_12"

        ]

    },

    {

        "name": "GPIO2_13",

        "gpio": 77,

        "mux": "lcd_data7",

        "eeprom": 52,

        "key": "P8_40",

        "muxRegOffset": "0x0bc",

        "options": [

            "lcd_data7",

            "gpmc_a7",

            "pr1_edio_data_in7",

            "eqep2_strobe",

            "pr1_pru1_pru_r30_7",

            "pr1_pru_pru1_r30_7",

            "pr1_pru1_pru_r31_7",

            "gpio2_13"

        ]

    },

    {

        "name": "GPIO2_10",

        "gpio": 74,

        "mux": "lcd_data4",

        "eeprom": 49,

        "key": "P8_41",

        "muxRegOffset": "0x0b0",

        "options": [

            "lcd_data4",

            "gpmc_a4",

            "pr1_mii0_txd1",

            "eQEP2A_in",

            "NA",

            "pr1_pru1_pru_r30_4",

            "pr1_pru1_pru_r31_4",

            "gpio2_10"

        ]

    },

    {

        "name": "GPIO2_11",

        "gpio": 75,

        "mux": "lcd_data5",

        "eeprom": 50,

        "key": "P8_42",

        "muxRegOffset": "0x0b4",

        "options": [

            "lcd_data5",

            "gpmc_a5",

            "pr1_mii0_txd0",

            "eqep2b_in",

            "NA",

            "pr1_pru1_pru_r30_5",

            "pr1_pru1_pru_r31_5",

            "gpio2_11"

        ]

    },

    {

        "name": "GPIO2_8",

        "gpio": 72,

        "mux": "lcd_data2",

        "eeprom": 47,

        "key": "P8_43",

        "muxRegOffset": "0x0a8",

        "options": [

            "lcd_data2",

            "gpmc_a2",

            "pr1_mii0_txd3",

            "ehrpwm2_tripzone_input",

            "NA",

            "pr1_pru1_pru_r30_2",

            "pr1_pru1_pru_r31_2",

            "gpio2_8"

        ]

    },

    {

        "name": "GPIO2_9",

        "gpio": 73,

        "mux": "lcd_data3",

        "eeprom": 48,

        "key": "P8_44",

        "muxRegOffset": "0x0ac",

        "options": [

            "lcd_data3",

            "gpmc_a3",

            "pr1_mii0_txd2",

            "ehrpwm0_synco",

            "NA",

            "pr1_pru1_pru_r30_3",

            "pr1_pru1_pru_r31_3",

            "gpio2_9"

        ]

    },

    {

        "name": "GPIO2_6",

        "gpio": 70,

        "mux": "lcd_data0",

        "eeprom": 45,

        "pwm": {

            "module": "ehrpwm2",

            "index": 0,

            "muxmode": 3,

            "path": "ehrpwm.2:0",

            "name": "EHRPWM2A"

        },

        "key": "P8_45",

        "muxRegOffset": "0x0a0",

        "options": [

            "lcd_data0",

            "gpmc_a0",

            "pr1_mii_mt0_clk",

            "ehrpwm2A",

            "NA",

            "pr1_pru1_pru_r30_0",

            "pr1_pru1_pru_r31_0",

            "gpio2_6"

        ]

    },

    {

        "name": "GPIO2_7",

        "gpio": 71,

        "mux": "lcd_data1",

        "eeprom": 46,

        "pwm": {

            "module": "ehrpwm2",

            "index": 1,

            "muxmode": 3,

            "path": "ehrpwm.2:1",

            "name": "EHRPWM2B"

        },

        "key": "P8_46",

        "muxRegOffset": "0x0a4",

        "options": [

            "lcd_data1",

            "gpmc_a1",

            "pr1_mii0_txen",

            "ehrpwm2B",

            "NA",

            "pr1_pru1_pru_r30_1",

            "pr1_pru1_pru_r31_1",

            "gpio2_7"

        ]

    },

    {

        "name": "DGND",

        "key": "P9_1"

    },

    {

        "name": "DGND",

        "key": "P9_2"

    },

    {

        "name": "VDD_3V3",

        "key": "P9_3"

    },

    {

        "name": "VDD_3V3",

        "key": "P9_4"

    },

    {

        "name": "VDD_5V",

        "key": "P9_5"

    },

    {

        "name": "VDD_5V",

        "key": "P9_6"

    },

    {

        "name": "SYS_5V",

        "key": "P9_7"

    },

    {

        "name": "SYS_5V",

        "key": "P9_8"

    },

    {

        "name": "PWR_BUT",

        "key": "P9_9"

    },

    {

        "name": "SYS_RESETn",

        "key": "P9_10"

    },

    {

        "name": "UART4_RXD",

        "gpio": 30,

        "mux": "gpmc_wait0",

        "eeprom": 18,

        "key": "P9_11",

        "muxRegOffset": "0x070",

        "options": [

            "gpmc_wait0",

            "mii2_crs",

            "NA",

            "rmii2_crs_dv",

            "mmc1_sdcd",

            "NA",

            "NA",

            "gpio0_30"

        ]

    },

    {

        "name": "GPIO1_28",

        "gpio": 60,

        "mux": "gpmc_ben1",

        "eeprom": 36,

        "key": "P9_12",

        "muxRegOffset": "0x078",

        "options": [

            "gpmc_ben1",

            "mii2_col",

            "NA",

            "mmc2_dat3",

            "NA",

            "NA",

            "mcasp0_aclkr",

            "gpio1_28"

        ]

    },

    {

        "name": "UART4_TXD",

        "gpio": 31,

        "mux": "gpmc_wpn",

        "eeprom": 19,

        "key": "P9_13",

        "muxRegOffset": "0x074",

        "options": [

            "gpmc_wpn",

            "mii2_rxerr",

            "NA",

            "rmii2_rxerr",

            "mmc2_sdcd",

            "NA",

            "NA",

            "gpio0_31"

        ]

    },

    {

        "name": "EHRPWM1A",

        "gpio": 50,

        "mux": "gpmc_a2",

        "eeprom": 34,

        "pwm": {

            "module": "ehrpwm1",

            "index": 0,

            "muxmode": 6,

            "path": "ehrpwm.1:0",

            "name": "EHRPWM1A"

        },

        "key": "P9_14",

        "muxRegOffset": "0x048",

        "options": [

            "gpmc_a2",

            "gmii2_txd3",

            "rgmii2_td3",

            "mmc2_dat1",

            "gpmc_a18",

            "pr1_mii1_txd2",

            "ehrpwm1A",

            "gpio1_18"

        ]

    },

    {

        "name": "GPIO1_16",

        "gpio": 48,

        "mux": "mii1_rxd3",

        "eeprom": 32,

        "key": "P9_15",

        "muxRegOffset": "0x040",

        "options": [

            "gpmc_a0",

            "gmii2_txen",

            "rgmii2_tctl",

            "rmii2_txen",

            "gpmc_a16",

            "pr1_mii_mt1_clk",

            "ehrpwm1_tripzone_input",

            "gpio1_16"

        ]

    },

    {

        "name": "EHRPWM1B",

        "gpio": 51,

        "mux": "gpmc_a3",

        "eeprom": 35,

        "pwm": {

            "module": "ehrpwm1",

            "index": 1,

            "muxmode": 6,

            "path": "ehrpwm.1:1",

            "name": "EHRPWM1B"

        },

        "key": "P9_16",

        "muxRegOffset": "0x04c",

        "options": [

            "gpmc_a3",

            "gmii2_txd2",

            "rgmii2_td2",

            "mmc2_dat2",

            "gpmc_a19",

            "pr1_mii1_txd1",

            "ehrpwm1B",

            "gpio1_19"

        ]

    },

    {

        "name": "I2C1_SCL",

        "gpio": 5,

        "mux": "spi0_cs0",

        "eeprom": 3,

        "key": "P9_17",

        "muxRegOffset": "0x15c",

        "options": [

            "spi0_cs0",

            "mmc2_sdwp",

            "i2c1_scl",

            "NA",

            "NA",

            "NA",

            "NA",

            "gpio0_5"

        ]

    },

    {

        "name": "I2C1_SDA",

        "gpio": 4,

        "mux": "spi0_d1",

        "eeprom": 2,

        "key": "P9_18",

        "muxRegOffset": "0x158",

        "options": [

            "spi0_d1",

            "mmc1_sdwp",

            "i2c1_sda",

            "NA",

            "NA",

            "NA",

            "NA",

            "gpio0_4"

        ]

    },

    {

        "name": "I2C2_SCL",

        "gpio": 13,

        "mux": "uart1_rtsn",

        "eeprom": 9,

        "key": "P9_19",

        "muxRegOffset": "0x17c",

        "options": [

            "uart1_rtsn",

            "NA",

            "d_can0_rx",

            "i2c2_scl",

            "spi1_cs1",

            "NA",

            "NA",

            "gpio0_13"

        ]

    },

    {

        "name": "I2C2_SDA",

        "gpio": 12,

        "mux": "uart1_ctsn",

        "eeprom": 10,

        "key": "P9_20",

        "muxRegOffset": "0x178",

        "options": [

            "uart1_ctsn",

            "NA",

            "d_can0_tx",

            "i2c2_sda",

            "spi1_cs0",

            "NA",

            "NA",

            "gpio0_12"

        ]

    },

    {

        "name": "UART2_TXD",

        "gpio": 3,

        "mux": "spi0_d0",

        "eeprom": 1,

        "pwm": {

            "module": "ehrpwm0",

            "index": 1,

            "muxmode": 3,

            "path": "ehrpwm.0:1",

            "name": "EHRPWM0B"

        },

        "key": "P9_21",

        "muxRegOffset": "0x154",

        "options": [

            "spi0_d0",

            "uart2_txd",

            "i2c2_scl",

            "NA",

            "NA",

            "NA",

            "NA",

            "gpio0_3"

        ]

    },

    {

        "name": "UART2_RXD",

        "gpio": 2,

        "mux": "spi0_sclk",

        "eeprom": 0,

        "pwm": {

            "module": "ehrpwm0",

            "index": 0,

            "muxmode": 3,

            "path": "ehrpwm.0:0",

            "name": "EHRPWM0A"

        },

        "key": "P9_22",

        "muxRegOffset": "0x150",

        "options": [

            "spi0_sclk",

            "uart2_rxd",

            "i2c2_sda",

            "NA",

            "NA",

            "NA",

            "NA",

            "gpio0_2"

        ]

    },

    {

        "name": "GPIO1_17",

        "gpio": 49,

        "mux": "gpmc_a1",

        "eeprom": 33,

        "key": "P9_23",

        "muxRegOffset": "0x044",

        "options": [

            "gpmc_a1",

            "gmii2_rxdv",

            "rgmii2_rctl",

            "mmc2_dat0",

            "gpmc_a17",

            "pr1_mii1_txd3",

            "ehrpwm0_synco",

            "gpio1_17"

        ]

    },

    {

        "name": "UART1_TXD",

        "gpio": 15,

        "mux": "uart1_txd",

        "eeprom": 12,

        "key": "P9_24",

        "muxRegOffset": "0x184",

        "options": [

            "uart1_txd",

            "mmc2_sdwp",

            "d_can1_rx",

            "i2c1_scl",

            "NA",

            "pr1_uart0_txd_mux1",

            "NA",

            "gpio0_15"

        ]

    },

    {

        "name": "GPIO3_21",

        "gpio": 117,

        "mux": "mcasp0_ahclkx",

        "eeprom": 66,

        "key": "P9_25",

        "muxRegOffset": "0x1ac",

        "options": [

            "mcasp0_ahclkx",

            "NA",

            "mcasp0_axr3",

            "mcasp1_axr1",

            "NA",

            "NA",

            "NA",

            "gpio3_21"

        ]

    },

    {

        "name": "UART1_RXD",

        "gpio": 14,

        "mux": "uart1_rxd",

        "eeprom": 11,

        "key": "P9_26",

        "muxRegOffset": "0x180",

        "options": [

            "uart1_rxd",

            "mmc1_sdwp",

            "d_can1_tx",

            "i2c1_sda",

            "NA",

            "pr1_uart0_rxd_mux1",

            "NA",

            "gpio0_14"

        ]

    },

    {

        "name": "GPIO3_19",

        "gpio": 115,

        "mux": "mcasp0_fsr",

        "eeprom": 64,

        "key": "P9_27",

        "muxRegOffset": "0x1a4",

        "options": [

            "mcasp0_fsr",

            "NA",

            "mcasp0_axr3",

            "mcasp1_fsx",

            "NA",

            "pr1_pru0_pru_r30_5",

            "NA",

            "gpio3_19"

        ]

    },

    {

        "name": "SPI1_CS0",

        "gpio": 113,

        "mux": "mcasp0_ahclkr",

        "eeprom": 63,

        "pwm": {

            "module": "ecap2",

            "index": 2,

            "muxmode": 4,

            "path": "ecap.2",

            "name": "ECAPPWM2"

        },

        "key": "P9_28",

        "muxRegOffset": "0x19c",

        "options": [

            "mcasp0_ahclkr",

            "NA",

            "mcasp0_axr2",

            "spi1_cs0",

            "eCAP2_in_PWM2_out",

            "NA",

            "NA",

            "gpio3_17"

        ]

    },

    {

        "name": "SPI1_D0",

        "gpio": 111,

        "mux": "mcasp0_fsx",

        "eeprom": 61,

        "pwm": {

            "module": "ehrpwm0",

            "index": 1,

            "muxmode": 1,

            "path": "ehrpwm.0:1",

            "name": "EHRPWM0B"

        },

        "key": "P9_29",

        "muxRegOffset": "0x194",

        "options": [

            "mcasp0_fsx",

            "ehrpwm0B",

            "NA",

            "spi1_d0",

            "mmc1_sdcd",

            "NA",

            "NA",

            "gpio3_15"

        ]

    },

    {

        "name": "SPI1_D1",

        "gpio": 112,

        "mux": "mcasp0_axr0",

        "eeprom": 62,

        "key": "P9_30",

        "muxRegOffset": "0x198",

        "options": [

            "mcasp0_axr0",

            "NA",

            "NA",

            "spi1_d1",

            "mmc2_sdcd",

            "NA",

            "NA",

            "gpio3_16"

        ]

    },

    {

        "name": "SPI1_SCLK",

        "gpio": 110,

        "mux": "mcasp0_aclkx",

        "eeprom": 65,

        "pwm": {

            "module": "ehrpwm0",

            "index": 0,

            "muxmode": 1,

            "path": "ehrpwm.0:0",

            "name": "EHRPWM0A"

        },

        "key": "P9_31",

        "muxRegOffset": "0x190",

        "options": [

            "mcasp0_aclkx",

            "ehrpwm0A",

            "NA",

            "spi1_sclk",

            "mmc0_sdcd",

            "NA",

            "NA",

            "gpio3_14"

        ]

    },

    {

        "name": "VDD_ADC",

        "key": "P9_32"

    },

    {

        "name": "AIN4",

        "ain": 4,

        "eeprom": 71,

        "scale": 4096,

        "key": "P9_33"

    },

    {

        "name": "GNDA_ADC",

        "key": "P9_34"

    },

    {

        "name": "AIN6",

        "ain": 6,

        "eeprom": 73,

        "scale": 4096,

        "key": "P9_35"

    },

    {

        "name": "AIN5",

        "ain": 5,

        "eeprom": 72,

        "scale": 4096,

        "key": "P9_36"

    },

    {

        "name": "AIN2",

        "ain": 2,

        "eeprom": 69,

        "scale": 4096,

        "key": "P9_37"

    },

    {

        "name": "AIN3",

        "ain": 3,

        "eeprom": 70,

        "scale": 4096,

        "key": "P9_38"

    },

    {

        "name": "AIN0",

        "ain": 0,

        "eeprom": 67,

        "scale": 4096,

        "key": "P9_39"

    },

    {

        "name": "AIN1",

        "ain": 1,

        "eeprom": 68,

        "scale": 4096,

        "key": "P9_40"

    },

    {

        "name": "CLKOUT2",

        "gpio": 20,

        "mux": "xdma_event_intr1",

        "eeprom": 13,

        "key": "P9_41",

        "muxRegOffset": "0x1b4",

        "options": [

            "xdma_event_intr1",

            "NA",

            "NA",

            "clkout2",

            "NA",

            "NA",

            "NA",

            "gpio0_20"

        ]

    },

    {

        "name": "GPIO0_7",

        "gpio": 7,

        "mux": "ecap0_in_pwm0_out",

        "eeprom": 4,

        "pwm": {

            "module": "ecap0",

            "index": 0,

            "muxmode": 0,

            "path": "ecap.0",

            "name": "ECAPPWM0"

        },

        "key": "P9_42",

        "muxRegOffset": "0x164",

        "options": [

            "eCAP0_in_PWM0_out",

            "uart3_txd",

            "spi1_cs1",

            "pr1_ecap0_ecap_capin_apwm_o",

            "spi1_sclk",

            "mmc0_sdwp",

            "xdma_event_intr2",

            "gpio0_7"

        ]

    },

    {

        "name": "DGND",

        "key": "P9_43"

    },

    {

        "name": "DGND",

        "key": "P9_44"

    },

    {

        "name": "DGND",

        "key": "P9_45"

    },

    {

        "name": "DGND",

        "key": "P9_46"

    }

];

 

var pins = {};

for(var i in pinIndex) {

    pins[pinIndex[i].key] = pinIndex[i];

}

 

var uarts = {

    "/dev/ttyO0": {

    },

    "/dev/ttyO1": {

        "devicetree": "BB-UART1",

        "rx": "P9_26",

        "tx": "P9_24"

    },

    "/dev/ttyO2": {

        "devicetree": "BB-UART2",

        "rx": "P9_22",

        "tx": "P9_21"

    },

    "/dev/ttyO3": {

    },

    "/dev/ttyO4": {

        "devicetree": "BB-UART4",

        "rx": "P9_11",

        "tx": "P9_13"

    },

    "/dev/ttyO5": {

        "devicetree": "BB-UART5",

        "rx": "P8_38",

        "tx": "P8_37"

    }

};

 

var i2c = {

    "/dev/i2c-0": {

    },

    "/dev/i2c-1": {

        "devicetree": "BB-I2C1",

        "path": "/dev/i2c-2",

        "sda": "P9_18",

        "scl": "P9_17"

    },

    "/dev/i2c-1a": {

        "devicetree": "BB-I2C1A",

        "path": "/dev/i2c-2",

        "sda": "P9_26",

        "scl": "P9_24"

    },

    "/dev/i2c-2": {

        "path": "/dev/i2c-1",

        "sda": "P9_20",

        "scl": "P9_19"

    }

};

 

exports.pins = pins;

exports.pinIndex = pinIndex;

exports.uarts = uarts;

exports.i2c = i2c;

 

 

 

GPIO handles/files

 

Even though the most of the information listed here will be there in most of Beaglebone board, the exact filename and path would be different depending on what kind of board you have (e.g, Beaglebone Black vs Beaglebone Gree) or which Linux kernel is installed on the board. So the most important thing is not to blindly copy the information listed in this page, but to know how to find these information in the specific Linux kernel on the board.  I will try to write down the tricks that I used to find these information for my board. I would suggest you to try the same tricks rather than just doing copy and paste.

 

In my case, following kernel was installed on the board

 

    Linux beaglebone 3.8.13-bone71.1 #1 SMP Wed May 20 20:13:27 PDT 2015 armv7l GNU/Linux

 

 

LED (USR) files

 

The first thing that I did was to find some hints of the location using ls -R and grep command as shown below.

 

root@beaglebone:/# cd /    <== This is to move to the rool directory

 

root@beaglebone:/# ls -al -R | grep "leds"  <== don't use "led", it would print out too much

 

./proc/device-tree/ocp/gpio-leds:

./proc/device-tree/ocp/gpio-leds/led0:

./proc/device-tree/ocp/gpio-leds/led1:

./proc/device-tree/ocp/gpio-leds/led2:

./proc/device-tree/ocp/gpio-leds/led3:

 

......

 

drwxr-xr-x  4 root root    0 Jan  1  2000 gpio-leds.8

./sys/devices/ocp.3/gpio-leds.8:

lrwxrwxrwx  1 root root    0 Mar  1 21:21 driver -> ../../../bus/platform/drivers/leds-gpio

drwxr-xr-x  6 root root    0 Jan  1  2000 leds

./sys/devices/ocp.3/gpio-leds.8/leds:

./sys/devices/ocp.3/gpio-leds.8/leds/beaglebone:green:usr0:

lrwxrwxrwx 1 root root    0 Mar  1 20:54 device -> ../../../gpio-leds.8

lrwxrwxrwx 1 root root    0 Jan  1  2000 subsystem -> ../../../../../class/leds

./sys/devices/ocp.3/gpio-leds.8/leds/beaglebone:green:usr0/power:

./sys/devices/ocp.3/gpio-leds.8/leds/beaglebone:green:usr1:

lrwxrwxrwx 1 root root    0 Mar  1 20:54 device -> ../../../gpio-leds.8

lrwxrwxrwx 1 root root    0 Jan  1  2000 subsystem -> ../../../../../class/leds

./sys/devices/ocp.3/gpio-leds.8/leds/beaglebone:green:usr1/power:

./sys/devices/ocp.3/gpio-leds.8/leds/beaglebone:green:usr2:

lrwxrwxrwx 1 root root    0 Mar  1 20:54 device -> ../../../gpio-leds.8

lrwxrwxrwx 1 root root    0 Jan  1  2000 subsystem -> ../../../../../class/leds

./sys/devices/ocp.3/gpio-leds.8/leds/beaglebone:green:usr2/power:

./sys/devices/ocp.3/gpio-leds.8/leds/beaglebone:green:usr3:

lrwxrwxrwx 1 root root    0 Mar  1 20:54 device -> ../../../gpio-leds.8

lrwxrwxrwx 1 root root    0 Jan  1  2000 subsystem -> ../../../../../class/leds

./sys/devices/ocp.3/gpio-leds.8/leds/beaglebone:green:usr3/power:

./sys/devices/ocp.3/gpio-leds.8/power:

 

....

 

From the result shown above and reading some pages on the web, I figured out '/sys/devices/ocp.3/gpio-leds.8/leds' would be the directory where USR leds files are located.

 

 

root@beaglebone:/# ls /sys/devices/ocp.3/gpio-leds.8/leds -al -R

 

/sys/devices/ocp.3/gpio-leds.8/leds:

total 0

drwxr-xr-x 6 root root 0 Jan  1  2000 .

drwxr-xr-x 4 root root 0 Jan  1  2000 ..

drwxr-xr-x 3 root root 0 Jan  1  2000 beaglebone:green:usr0

drwxr-xr-x 3 root root 0 Jan  1  2000 beaglebone:green:usr1

drwxr-xr-x 3 root root 0 Jan  1  2000 beaglebone:green:usr2

drwxr-xr-x 3 root root 0 Jan  1  2000 beaglebone:green:usr3

 

/sys/devices/ocp.3/gpio-leds.8/leds/beaglebone:green:usr0:

total 0

drwxr-xr-x 3 root root    0 Jan  1  2000 .

drwxr-xr-x 6 root root    0 Jan  1  2000 ..

-rw-r--r-- 1 root root 4096 Mar  1 20:54 brightness

lrwxrwxrwx 1 root root    0 Mar  1 20:54 device -> ../../../gpio-leds.8

-r--r--r-- 1 root root 4096 Mar  1 20:54 max_brightness

drwxr-xr-x 2 root root    0 Mar  1 20:50 power

lrwxrwxrwx 1 root root    0 Jan  1  2000 subsystem -> ../../../../../class/leds

-rw-r--r-- 1 root root 4096 Mar  1 20:54 trigger

-rw-r--r-- 1 root root 4096 Jan  1  2000 uevent

 

/sys/devices/ocp.3/gpio-leds.8/leds/beaglebone:green:usr0/power:

total 0

drwxr-xr-x 2 root root    0 Mar  1 20:50 .

drwxr-xr-x 3 root root    0 Jan  1  2000 ..

-rw-r--r-- 1 root root 4096 Mar  1 20:54 autosuspend_delay_ms

-rw-r--r-- 1 root root 4096 Mar  1 20:54 control

-r--r--r-- 1 root root 4096 Mar  1 20:54 runtime_active_time

-r--r--r-- 1 root root 4096 Mar  1 20:54 runtime_status

-r--r--r-- 1 root root 4096 Mar  1 20:54 runtime_suspended_time

 

/sys/devices/ocp.3/gpio-leds.8/leds/beaglebone:green:usr1:

total 0

drwxr-xr-x 3 root root    0 Jan  1  2000 .

drwxr-xr-x 6 root root    0 Jan  1  2000 ..

-rw-r--r-- 1 root root 4096 Mar  1 20:54 brightness

lrwxrwxrwx 1 root root    0 Mar  1 20:54 device -> ../../../gpio-leds.8

-r--r--r-- 1 root root 4096 Mar  1 20:54 max_brightness

drwxr-xr-x 2 root root    0 Mar  1 20:50 power

lrwxrwxrwx 1 root root    0 Jan  1  2000 subsystem -> ../../../../../class/leds

-rw-r--r-- 1 root root 4096 Mar  1 20:54 trigger

-rw-r--r-- 1 root root 4096 Jan  1  2000 uevent

 

/sys/devices/ocp.3/gpio-leds.8/leds/beaglebone:green:usr1/power:

total 0

drwxr-xr-x 2 root root    0 Mar  1 20:50 .

drwxr-xr-x 3 root root    0 Jan  1  2000 ..

-rw-r--r-- 1 root root 4096 Mar  1 20:54 autosuspend_delay_ms

-rw-r--r-- 1 root root 4096 Mar  1 20:54 control

-r--r--r-- 1 root root 4096 Mar  1 20:54 runtime_active_time

-r--r--r-- 1 root root 4096 Mar  1 20:54 runtime_status

-r--r--r-- 1 root root 4096 Mar  1 20:54 runtime_suspended_time

 

/sys/devices/ocp.3/gpio-leds.8/leds/beaglebone:green:usr2:

total 0

drwxr-xr-x 3 root root    0 Jan  1  2000 .

drwxr-xr-x 6 root root    0 Jan  1  2000 ..

-rw-r--r-- 1 root root 4096 Mar  1 20:54 brightness

lrwxrwxrwx 1 root root    0 Mar  1 20:54 device -> ../../../gpio-leds.8

-r--r--r-- 1 root root 4096 Mar  1 20:54 max_brightness

drwxr-xr-x 2 root root    0 Mar  1 20:50 power

lrwxrwxrwx 1 root root    0 Jan  1  2000 subsystem -> ../../../../../class/leds

-rw-r--r-- 1 root root 4096 Mar  1 20:54 trigger

-rw-r--r-- 1 root root 4096 Jan  1  2000 uevent

 

/sys/devices/ocp.3/gpio-leds.8/leds/beaglebone:green:usr2/power:

total 0

drwxr-xr-x 2 root root    0 Mar  1 20:50 .

drwxr-xr-x 3 root root    0 Jan  1  2000 ..

-rw-r--r-- 1 root root 4096 Mar  1 20:54 autosuspend_delay_ms

-rw-r--r-- 1 root root 4096 Mar  1 20:54 control

-r--r--r-- 1 root root 4096 Mar  1 20:54 runtime_active_time

-r--r--r-- 1 root root 4096 Mar  1 20:54 runtime_status

-r--r--r-- 1 root root 4096 Mar  1 20:54 runtime_suspended_time

 

/sys/devices/ocp.3/gpio-leds.8/leds/beaglebone:green:usr3:

total 0

drwxr-xr-x 3 root root    0 Jan  1  2000 .

drwxr-xr-x 6 root root    0 Jan  1  2000 ..

-rw-r--r-- 1 root root 4096 Mar  1 20:54 brightness

lrwxrwxrwx 1 root root    0 Mar  1 20:54 device -> ../../../gpio-leds.8

-r--r--r-- 1 root root 4096 Mar  1 20:54 max_brightness

drwxr-xr-x 2 root root    0 Mar  1 20:50 power

lrwxrwxrwx 1 root root    0 Jan  1  2000 subsystem -> ../../../../../class/leds

-rw-r--r-- 1 root root 4096 Mar  1 20:54 trigger

-rw-r--r-- 1 root root 4096 Jan  1  2000 uevent

 

/sys/devices/ocp.3/gpio-leds.8/leds/beaglebone:green:usr3/power:

total 0

drwxr-xr-x 2 root root    0 Mar  1 20:50 .

drwxr-xr-x 3 root root    0 Jan  1  2000 ..

-rw-r--r-- 1 root root 4096 Mar  1 20:54 autosuspend_delay_ms

-rw-r--r-- 1 root root 4096 Mar  1 20:54 control

-r--r--r-- 1 root root 4096 Mar  1 20:54 runtime_active_time

-r--r--r-- 1 root root 4096 Mar  1 20:54 runtime_status

-r--r--r-- 1 root root 4096 Mar  1 20:54 runtime_suspended_time

 

 

Default GPIO Files

 

 

root@beaglebone:/# ls /sys/class/gpio -al -R

/sys/class/gpio:

total 0

drwxr-xr-x  2 root root    0 Jan  1  2000 .

drwxr-xr-x 59 root root    0 Jan  1  2000 ..

--w-------  1 root root 4096 Jan  1  2000 export

lrwxrwxrwx  1 root root    0 Jan  1  2000 gpiochip0 -> ../../devices/virtual/gpio/gpiochip0

lrwxrwxrwx  1 root root    0 Jan  1  2000 gpiochip32 -> ../../devices/virtual/gpio/gpiochip32

lrwxrwxrwx  1 root root    0 Jan  1  2000 gpiochip64 -> ../../devices/virtual/gpio/gpiochip64

lrwxrwxrwx  1 root root    0 Jan  1  2000 gpiochip96 -> ../../devices/virtual/gpio/gpiochip96

--w-------  1 root root 4096 Jan  1  2000 unexport

 

 

root@beaglebone:/# ls /sys/devices/virtual/gpio -al -R

/sys/devices/virtual/gpio:

total 0

drwxr-xr-x  6 root root 0 Jan  1  2000 .

drwxr-xr-x 17 root root 0 Jan  1  2000 ..

drwxr-xr-x  3 root root 0 Jan  1  2000 gpiochip0

drwxr-xr-x  3 root root 0 Jan  1  2000 gpiochip32

drwxr-xr-x  3 root root 0 Jan  1  2000 gpiochip64

drwxr-xr-x  3 root root 0 Jan  1  2000 gpiochip96

 

/sys/devices/virtual/gpio/gpiochip0:

total 0

drwxr-xr-x 3 root root    0 Jan  1  2000 .

drwxr-xr-x 6 root root    0 Jan  1  2000 ..

-r--r--r-- 1 root root 4096 Mar  1 21:09 base

-r--r--r-- 1 root root 4096 Mar  1 21:09 label

-r--r--r-- 1 root root 4096 Mar  1 21:09 ngpio

drwxr-xr-x 2 root root    0 Mar  1 21:09 power

lrwxrwxrwx 1 root root    0 Jan  1  2000 subsystem -> ../../../../class/gpio

-rw-r--r-- 1 root root 4096 Jan  1  2000 uevent

 

/sys/devices/virtual/gpio/gpiochip0/power:

total 0

drwxr-xr-x 2 root root    0 Mar  1 21:09 .

drwxr-xr-x 3 root root    0 Jan  1  2000 ..

-rw-r--r-- 1 root root 4096 Mar  1 21:09 autosuspend_delay_ms

-rw-r--r-- 1 root root 4096 Mar  1 21:09 control

-r--r--r-- 1 root root 4096 Mar  1 21:09 runtime_active_time

-r--r--r-- 1 root root 4096 Mar  1 21:09 runtime_status

-r--r--r-- 1 root root 4096 Mar  1 21:09 runtime_suspended_time

 

/sys/devices/virtual/gpio/gpiochip32:

total 0

drwxr-xr-x 3 root root    0 Jan  1  2000 .

drwxr-xr-x 6 root root    0 Jan  1  2000 ..

-r--r--r-- 1 root root 4096 Mar  1 21:09 base

-r--r--r-- 1 root root 4096 Mar  1 21:09 label

-r--r--r-- 1 root root 4096 Mar  1 21:09 ngpio

drwxr-xr-x 2 root root    0 Mar  1 21:09 power

lrwxrwxrwx 1 root root    0 Jan  1  2000 subsystem -> ../../../../class/gpio

-rw-r--r-- 1 root root 4096 Jan  1  2000 uevent

 

/sys/devices/virtual/gpio/gpiochip32/power:

total 0

drwxr-xr-x 2 root root    0 Mar  1 21:09 .

drwxr-xr-x 3 root root    0 Jan  1  2000 ..

-rw-r--r-- 1 root root 4096 Mar  1 21:09 autosuspend_delay_ms

-rw-r--r-- 1 root root 4096 Mar  1 21:09 control

-r--r--r-- 1 root root 4096 Mar  1 21:09 runtime_active_time

-r--r--r-- 1 root root 4096 Mar  1 21:09 runtime_status

-r--r--r-- 1 root root 4096 Mar  1 21:09 runtime_suspended_time

 

/sys/devices/virtual/gpio/gpiochip64:

total 0

drwxr-xr-x 3 root root    0 Jan  1  2000 .

drwxr-xr-x 6 root root    0 Jan  1  2000 ..

-r--r--r-- 1 root root 4096 Mar  1 21:09 base

-r--r--r-- 1 root root 4096 Mar  1 21:09 label

-r--r--r-- 1 root root 4096 Mar  1 21:09 ngpio

drwxr-xr-x 2 root root    0 Mar  1 21:09 power

lrwxrwxrwx 1 root root    0 Jan  1  2000 subsystem -> ../../../../class/gpio

-rw-r--r-- 1 root root 4096 Jan  1  2000 uevent

 

/sys/devices/virtual/gpio/gpiochip64/power:

total 0

drwxr-xr-x 2 root root    0 Mar  1 21:09 .

drwxr-xr-x 3 root root    0 Jan  1  2000 ..

-rw-r--r-- 1 root root 4096 Mar  1 21:09 autosuspend_delay_ms

-rw-r--r-- 1 root root 4096 Mar  1 21:09 control

-r--r--r-- 1 root root 4096 Mar  1 21:09 runtime_active_time

-r--r--r-- 1 root root 4096 Mar  1 21:09 runtime_status

-r--r--r-- 1 root root 4096 Mar  1 21:09 runtime_suspended_time

 

/sys/devices/virtual/gpio/gpiochip96:

total 0

drwxr-xr-x 3 root root    0 Jan  1  2000 .

drwxr-xr-x 6 root root    0 Jan  1  2000 ..

-r--r--r-- 1 root root 4096 Mar  1 21:09 base

-r--r--r-- 1 root root 4096 Mar  1 21:09 label

-r--r--r-- 1 root root 4096 Mar  1 21:09 ngpio

drwxr-xr-x 2 root root    0 Mar  1 21:09 power

lrwxrwxrwx 1 root root    0 Jan  1  2000 subsystem -> ../../../../class/gpio

-rw-r--r-- 1 root root 4096 Jan  1  2000 uevent

 

/sys/devices/virtual/gpio/gpiochip96/power:

total 0

drwxr-xr-x 2 root root    0 Mar  1 21:09 .

drwxr-xr-x 3 root root    0 Jan  1  2000 ..

-rw-r--r-- 1 root root 4096 Mar  1 21:09 autosuspend_delay_ms

-rw-r--r-- 1 root root 4096 Mar  1 21:09 control

-r--r--r-- 1 root root 4096 Mar  1 21:09 runtime_active_time

-r--r--r-- 1 root root 4096 Mar  1 21:09 runtime_status

-r--r--r-- 1 root root 4096 Mar  1 21:09 runtime_suspended_time

 

 

Reference :

 

[1] BeagleBone Black Development Board

[2] BeagleBone Development Board

[3] AM335x Sitara™ Processors Technical Reference Manual