GPIO

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The GPIO of BeagleBone Black/Green consists of P8 and P9 Expansion Headers as shown below.

Power, GND

Power source and GND for supplying power to external devices. You can also supply power to the BeagleBone board through the VDD 5V pin.

VDD 3.3V
VDD 5V *
SYS 5V
DGND

* VDD 5V is only available when 5V power is supplied through the barrel jack.

Digital I/O

Pins available for digital input or output. Some pins are dedicated for eMMC and HDMI use, so to use them as GPIO pins, you need to disable eMMC and HDMI functions. For detailed instructions, refer to here.

GPIO_xxx

When using digital I/O pins in Grablo, you must use the GPIO number, not the pin number. (The xxx in GPIO_xxx)

PWM

Pins for PWM output. Some pins are dedicated for eMMC and HDMI use, so to use them as PWM pins, you need to disable eMMC and HDMI functions. For detailed instructions, refer to here.

EHRPWM0A
EHRPWM0B
EHRPWM1A
EHRPWM1B
EHRPWM2A
EHRPWM2B
ECAPPWM0
ECAPPWM2

ADC

Analog to Digital Converter (ADC) pins. The voltage range is 0~1.8V.

AIN0~AIN6
VDD_ADC (1.8V)
GNDA_ADC

Be careful not to apply voltage exceeding 1.8V to AIN0~AIN6 pins as it may damage the board.

I2C

Pins for I2C communication. BeagleBone Black/Green provides 2 I2C ports.

I2C1_SCL, I2C1_SDA
I2C2_SCL, I2C2_SDA

SPI

Pins for SPI communication. BeagleBone Black/Green provides 2 SPI ports. SPI1 pins are dedicated for HDMI use, so to use them as SPI pins, you need to disable HDMI function. For detailed instructions, refer to here.

UART

Pins for UART communication. Some pins are dedicated for HDMI use, so to use them as UART pins, you need to disable HDMI function. For detailed instructions, refer to here.

UART1_RXD, UART1_TXD
UART2_RXD, UART2_TXD
UART3_TXD
UART5_RXD, UART5_TXD

eMMC, HDMI

Pins for eMMC and HDMI control. If you don’t use eMMC or HDMI, you can disable these functions to use the pins for other purposes.

MMC1_xxx
LCD_xxx
SPI1_xxx

Disabling eMMC and HDMI

Connect to the BeagleBone board via SSH.

Enter the following command:

sudo nano /boot/uEnv.txt

The file content will be displayed as follows:

##Disable auto loading of virtual capes (emmc/video/wireless/adc)
#Disable eMMC
disable_uboot_overlay_emmc=1 #Disable eMMC
#Disable HDMI
disable_uboot_overlay_video=1 #Disable HDMI
#Disable Audio
disable_uboot_overlay_audio=1 #Disable HDMI
#Disable Wireless
#disable_uboot_overlay_wireless=1
#Disable ADC
#disable_uboot_overlay_adc=1

To disable eMMC, uncomment #disable_uboot_overlay_emmc=1 by removing the # at the beginning.

To disable HDMI, uncomment #disable_uboot_overlay_video=1 and #disable_uboot_overlay_audio=1.

Press Ctrl + X to exit the editor.

Press Y to save the changes.

Enter the following command to reboot the BeagleBone and apply the changed settings:

sudo reboot