BeagleBone Black Hardware Overview
Updated: 17Aug2024 08:45:11 UTC 2024-08-17T08:45:11Z
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The BeagleBone Black (BBB) SBC is an open-source community-supported embedded computer for makers, developers, educators, and professionals looking to develop custom projects and solutions. This hardware overview of the BBB covers specs, board layout, pinout, processors, memory, I/O, and power.
The BBB SBC is a credit-card sized development platform with the following features.
- Processors:
-
- TITexas Instruments AM335x 1GHz ARM Cortex-A8 processor
- PowerVR SGX530 3D GPUGraphics Processing Unit
- 2x PRUProgrammable Real-time Unit 32-bit microcontrollers
- Memory:
-
- 512MB of DDRDouble Data Rate (DDR) is a type of SDRAM memory that fetches data on both the leading edge and the falling edge of the clock signal that regulates it.3L DRAMDynamic Random-Access Memory
- 4GB onboard eMMCEmbedded Multimedia Card flash memory with pre-installed Linux operating system (no microSD card required)
- microSD card slot as an alternative OS boot source and data storage
- I/O Ports:
-
- micro HDMIHigh-Definition Multimedia Interface port
- Type-A USBUniversal Serial Bus 2.0 port
- mini-USBclient
- 10/100 RJ45RJ45 is the most common type of the connector used for Ethernet networking. RJ stands for “Registered Jack” and 45 refers to the interface standard number. It has eight pins, which means that it contains eight separate wires. Ethernet port
- 20-pin CTI JTAGJoint Test Action Group pad for debugging using JTAGJoint Test Action Group emulators
- 2x 46-pin GPIOGeneral Purpose Input Output headers
The GPIO allows for the use of add-on boards called capes, to add many different combinations of features. The board comes with a 3ft USB-A to Mini-B USB Cable. Since the board has only one USB host port, you may need to use a USB Hub if your keyboard and mouse requires two ports. - Power:
- The BBB board can be powered using a 5V 2A DCDirect Current power supply using the 5.5mm (ODOuter Diameter) x 2.1mm (IDInner Diameter) barrel jack (center positive) on the top of the board or mini USB port on the bottom of the board. The top and bottom views of the board are shown below.
Specs
| Parameter | Description |
|---|---|
| Board Info | BeagleBone Black RevC |
| Processors |
TITexas Instruments AM3358 SoCSystem On a Chip
(AM335x Datasheet PDF)
|
| Memory |
|
| USB |
|
| Ethernet | 1x 10/100 RJ45RJ45 is the most common type of the connector used for Ethernet networking. RJ stands for “Registered Jack” and 45 refers to the interface standard number. It has eight pins, which means that it contains eight separate wires. Ethernet port |
| Wireless | There is no onboard WiFi or Bluetooth, but you can use the USBUniversal Serial Bus port with a WiFi/BTBluetooth USB Dongle |
| Video & Sound | 1x Micro HDMIHigh-Definition Multimedia Interface 1.4a port, supports EDIDExtended Display Identification Data and resolutions up to 1280x1024 @ 60fpsFrames Per Second or 1920x1080 @ 24fpsFrames Per Second |
| GPIO |
2x 46-pin GPIOGeneral Purpose Input Output headers with up to
|
| Debug I/O |
|
| User I/O |
|
| Power |
A minimum power supply of 5V 1A DC can be used to power the board by itself and a
5V 2A DC supply is recommended if powering external devices from the board.
The board can be powered through four different inputs:
Board has a TPS65217C PMICPower Management Integrated Circuit (PMIC) regulator and one additional LDOLow Dropout Regulator
|
| Board Size (LxW) | 86.36mm x 53.34mm (3.40in x 2.15in) |
Board Layout
Processors
The BeagleBone Black processors are integrated into a TITexas Instruments AM335x SoCSystem On a Chip with a Sitara 32-bit 1GHz ARM Cortex-A8 CPU, PowerVR SGX530 3D GPU, 2x PRU 32-bit 200MHz microcontrollers, and Crypto Accelerators (AESAdvanced Encryption Standard (AES) is a specification for the encryption of electronic data established by the U.S. National Institute of Standards and Technology (NIST) in 2001. It was developed an alternative to the Data Encryption Standard (DES), which was starting to become vulnerable to brute-force attacks., SHASecure Hash Algorithms (SHA) are a family of hashing functions used for hashing data and certificates, RNGRandom Number Generator).
BeagleBone Black boards used an XAM3359AZCZ100 processor, but more recent boards (from Rev C) use the AM3358BZCZ100. Full documentation for the AM3358 can be found on the TITexas Instruments website AM3358 Product Page and AM335x Datasheet (PDF).
CPU
The Sitara 32-bit 1GHz ARM Cortex-A8 CPUCentral Processing Unit performs operations such as basic arithmetic, logic, controlling, and I/OInput/Output. The ARM core has a NEON SIMD (Single Instruction Multiple Data) floating-point accelerator coprocessor.
During the execution of one instruction the same operation will occur on up to 16 data sets in parallel. This parallelism provides more MIPSMega (Million) Instructions Per Second or FLOPSFLoating point Operations Per Second than you can a standard SISD (Single Instruction, Single Data) processor running at the same clock rate. The ARM Cortex-A8 CPU provides up to 2000 MIPSMega (Million) Instructions Per Second.
GPU
The Imagination Technologies PowerVR SGX530 3D GPUGraphics Processing Unit offers 2 pixel and 1 vertex shaders that are usually clocked at 200MHz, a core processing of 1.6GFLOPSGiga (one billion) FLoating point Operations Per Second, a fillrate of 200MP/sMega (one million) Pixels per second, and is capable of rending 20 million polygons per second.
The PowerVR SGX530 3D GPU is not utilized in the BeagleBone Black by default (it's just sitting their doing nothing) and the CPU handles all multimedia tasks such as video and graphics. This GPU was licensed by TITexas Instruments from Imagination Technologies under a NDANon-Disclosure Agreement that prevents TITexas Instruments from publishing the details of this hardware. TITexas Instruments is only allowed to release a binary driver that would require a lot of effort on creating its own infrastructure to work on BeagleBone Black. Imagination Technologies has been working with the BeagleBoard.org Foundation to enable users to enhance applications with support for OpenGL ESOpen Graphics Library Embedded Systems or GLES 2.0 and OpenCLOpen Computing Language (OpenCL) is a framework for writing programs that execute across heterogeneous platforms consisting of central processing units (CPUs), graphics processing units (GPUs), digital signal processors (DSPs), field-programmable gate arrays (FPGAs) and other processors or hardware accelerators. 1.1.
PRU
The Programmable Real-time Units (PRUProgrammable Real-time Units) are small microcontroller (MCUMicrocontroller Units) processors that offer low-latency control of GPIOGeneral Purpose Input Output pins. A PRU has its own execution core and memory with a rich instruction set.
A computer time-sharing operating system, such as Linux, manages the sharing of system resources with a scheduler, data buffers, or fixed task prioritization in a multitasking environment. These operating systems are unsuited to critical hard real-time tasks with response requirements shorter than a millisecond while providing general purpose computer tasks such as web browsing, word processing, file system support, etc.
By using a PRU, you can achieve fast, deterministic, real-time control of I/OInput/Output pins and devices without bottlenecking the CPU. It can trigger or receive interrupts, accesses the PWMPulse-Width Modulations, read ADCAnalog-to-Digital Converter (ADC, A/D, or A-to-D)s values, or access the main memory for sharing with the CPU.
Memory
There are four memory components on the board outside the SoC: DDRDouble Data Rate (DDR) is a type of SDRAM memory that fetches data on both the leading edge and the falling edge of the clock signal that regulates it.3L RAMRandom Access Memory, eMMCEmbedded Multimedia Card, microSDThe microSD is a Secure Digital (SD) removable miniaturized flash memory card that is the compact version of a standard SD card and is meant to be used with smaller devices., and EEPROMElectrically Erasable Programmable Read-Only Memory. The DDR3L RAM chip is volatile memory used by the SoC, while the non-volatile memory is stored in a eMMC chip and an optional microSD card. The EEPROM is a small amount of memory that hold the board information.
RAM
The 512MB DDRDouble Data Rate (DDR) is a type of SDRAM memory that fetches data on both the leading edge and the falling edge of the clock signal that regulates it.3L 800MHz SDRAMSynchronous Dynamic Random-Access Memory chip can either be a Micron MT41K256M16TW-107:P or Kingston D2516EC4BXGGB-U, which interfaces to the SoC processor over 16 data lines, 16 address lines, and 14 control lines. It operates at a clock frequency of 400MHz, yielding an effective rate of 800MHZ on the DDR3L bus allowing for 1600Mbps of DDR3L memory bandwidth. DDR3L is known as DDR3 Low Voltage with a specification that is compatible with the original DDR3 standard with the additional capability of operating at a lower voltage.
eMMC
The 4GB 8-bit eMMCEmbedded Multimedia Card on-board flash storage chip could be either a Kingston MMC04G-M627-X02U, Kingston EMMC04G-S100-A08U, or Micron MTFC4GACAJCN-1M WT. The eMMC is the default OSOperating System boot mode that will allow for the fastest boot time and will enable the board to boot out of the box using the pre-installed OSOperating System image without having to purchase an microSDThe microSD is a Secure Digital (SD) removable miniaturized flash memory card that is the compact version of a standard SD card and is meant to be used with smaller devices. card or an microSD card writer.
The eMMC device connects to the MMC1 port of the SoC processor, allowing for 8bit wide access. The default boot mode for the board is set to MMC1, but you have the option to change it to MMC0 for booting from the microSD card by holding the boot switch button down while removing and reapplying power to the board. Without holding the boot switch, the board will try to boot from the eMMC. If it is empty, then it will try booting from the microSD slot, followed by the serial port, and then the USBUniversal Serial Bus port.
microSD
There is a single microSDThe microSD is a Secure Digital (SD) removable miniaturized flash memory card that is the compact version of a standard SD card and is meant to be used with smaller devices. connector on the bottom of the board to act as the secondary boot source for the board and, if selected as such, can be the primary boot source. The connector will support larger capacity microSD cards and can be used for data storage. The microSD card is not provided with the board and must be purchased separately.
EEPROM
A single 4KB EEPROMElectrically Erasable Programmable Read-Only Memory (24LC32AT-I/OT) is provided on I2C0 that holds the board information. This information includes board name, serial number, and revision information.
USB
The board consist of two USB ports: a mini USBUniversal Serial Bus port on the bottom of the board and a Type-A USB 2.0 port on the top of the board.
The mini USB port connects to the USB0 port of the processor and can be used to power the board with a 5V 2A DC supply and as a client for tethering to a PC. The board is sold with a 3ft Type-A to Mini-B USB cable. When tethered to a PCPersonal Computer via the USB cable the board can be accessed as a storage drive or a RNDISRemote Network Driver Interface Standard Ethernet connection (internet-over-USB that creates a private virtual LANLocal Area Network between the board and your desktop PC).
The Type-A USB 2.0 port on the top of the board connects to the USB1 port of the processor as a host port for peripherals, such as a wireless mouse and keyboard or USB WiFi/BTBluetooth. Since the board has only one USB host port, you may need to use a USB Hub if your keyboard and mouse requires two ports. The board can only supply up to 500mA at 5V, so if you plan to load it down, it will need to be externally powered.
Ethernet
The board has a single 10/100 RJ45RJ45 is the most common type of the connector used for Ethernet networking. RJ stands for “Registered Jack” and 45 refers to the interface standard number. It has eight pins, which means that it contains eight separate wires. Ethernet port with two LEDLight Emitting Diodes on the connector as status indicators. One LED is yellow (100M Link up if on) and the other LED is green (indicating traffic when flashing). The Ethernet port can be used to connect to a network by attaching an Ethernet cable to a router or directly to a PCPersonal Computer using an Ethernet crossover cable (i.e., a cable that has been modified to enable two Ethernet devices to be connected directly together without the need for an Ethernet switch).
By default, the board is configured to request a DHCPThe Dynamic Host Configuration Protocol (DHCP) is a network management protocol used on Internet Protocol (IP) networks for automatically assigning IP addresses and other communication parameters to devices connected to the network. IPInternet Protocol address. In a home network environment, this service is usually provided by a DHCP server that is running on an integrated modem-router that connects the home to an internet service provider (ISPIn-circuit Serial Programming or In-System Programming). DHCP servers issue IP addresses dynamically from a pool of addresses for a fixed time interval, called the lease time, specified in your DHCP configuration. However, it is possible to set the IP address of your board to be static so it has the same address every time the board connects.
Audio-Video
On the back of the board is a single mini HDMIHigh-Definition Multimedia Interface connector that carries sound and video to one display such as a computer monitor.
HDMI
The HDMIHigh-Definition Multimedia Interface port supports HDMI 1.4a, but does not support HDCPHigh-bandwidth Digital Content Protection (HDCP) is a form of digital copy protection to prevent copying of digital audio and video content as it travels across connections.. It can provide a maximum resolution of 1280x1024 @ 60fps or 1920x1080 @ 24fps. The HDMI port also supports EDIDExtended Display Identification Data, where the highest compatible resolution is selected automatically based on the EDID reading from the connected monitor.
The board has an NXP TDA19988BHN HDMI framer ICIntegrated Circuit (TDA19988 Datasheet PDF) that converts the LCDLiquid Crystal Display signals and audio signals to drive a HDMI monitor. A single HDMI interface is connected to the 16-bit LCD interface on the processor. The 16-bit interface was used to preserve as many expansion pins as possible to allow for use by the user. The signals are still connected to the expansion headers to enable the use of LCD expansion boards or access to other functions on the board as needed.
GPIO
The GPIOGeneral Purpose Input Output interface consists of two 46-pin female headers called P8 and P9, with 2.54mm (0.1in) pin spacing.
All signals on the GPIO headers are 3.3V (connecting 5V logic levels to these pins will be damage the board and you should never apply voltage to any I/OInput/Output pin when power is not supplied to the board because it will damage the processor). Many of the pins are multiplexed, which means they have more than one function. The board pin numbers, processor pin numbers, pin names, and the mode settings for each pin, are provided in tables for both P8 and P9 headers in the beaglebone.org documentation.
The GPIO headers consists of the following options:
- 4x 5V DCDirect Current input/output power pins
- 2x 3.3V DCDirect Current output power pins
- 8x GNDCommon Ground pins
- 65x Digital I/OInput/Output with 8x PWMPulse-Width Modulation and 4x Timers
- 7x analog inputs (12-bit ADCAnalog-to-Digital Converter (ADC, A/D, or A-to-D) 1.8V Max)
- 5x UARTUniversal Asynchronous Receiver-Transmitter
- 2x I2CInter-Integrated Circuit. Also referred to as IIC or I2C.
- 2x SPISerial Peripheral Interface
- 2x CANController Area Network (CAN) is a high-integrity serial communication bus designed for harsh environments such as industrial and automotive applications.
- 2x McASPMultichannel Audio Serial Port
- 2x MMCMultimedia Card
- 1x LCDLiquid Crystal Display
- 1x GPMCGeneral Purpose Memory Controller
- 1x Power Button
- 1x Reset Button
- Power Pins:
-
The power pins consist of 5V, 3.3V, and GND pins.
- VDD_5V (Header P9 on Pins 5 and 6) are directly tied to the barrel jack that can provide an output of 5V when a power supply is connected to the barrel jack or or used as an input to power the board from a well regulated 5V±0.25V DC power supply.
- SYS_5V (Header P9 on Pins 7 and 8) comes from the mini USB and used as output power for devices limited to 250mA.
- VDD_3V3B pins (Header P9 on Pins 3 and 4) are supplied by the LDOLow Dropout Regulator on the board and is the primary output power rail for expansion boards.
- DGND Common Ground pins (Header P8 on Pins 1, 2, 43, 44, 45, 46 and Header P9 on Pins 1 and 2)
- Digital I/OInput/Output Pins:
- Digital pins allow you to read or write HIGH or LOW voltage levels on the GPIO pin. They often have interrupts that can redirect processes on the CPU when events occur. Some of the Digital I/O are capable of Pulse-Width Modulation (PWMPulse-Width Modulation) used to generate pulses with a specified duty cycle to control the brightness of LEDLight Emitting Diodes, control motors, and can provide limited analog-like output. There are also four timers that are used to detect and/or capture external timing events or generate timing events to control external devices.
- Analog Pins:
- There are 7 analog pins that are channels on a single 12-bit ADCAnalog-to-Digital Converter (ADC, A/D, or A-to-D) that operates in the range of 0V to 1.8V, giving a resolution of 0.44mV.
- UARTUniversal Asynchronous Receiver-Transmitter:
- Universal Asynchronous Receiver-Transmitter (UARTUniversal Asynchronous Receiver-Transmitter) used for serial communication between different devices.
- I2CInter-Integrated Circuit. Also referred to as IIC or I2C.:
- Inter-Integrated Circuit (I2C) used for communicating with lower-speed peripheral devices like sensors and microcontrollers.
- SPISerial Peripheral Interface:
- Serial Peripheral Interface (SPI) used for communicating with higher-speed peripheral devices and allowing the daisy chaining of devices.
- CANController Area Network (CAN) is a high-integrity serial communication bus designed for harsh environments such as industrial and automotive applications.:
- Controller Area Network (CAN) buses provide high-speed external asynchronous data transfer. There are two internal CAN-Bus controllers which are called DCAN0 and DCAN1. However, only the DCAN1-interface should be used because the DCAN0 interface shares I/O pins with the I2C Bus for cape identification. The pins of the DCAN1-interface are multiplexed to the connector P9 pin 24 (CAN_RX) and 26 (CAN_TX). The AM335x DCAN controller is used to send and receive messages to and from a CAN Bus using Linux SocketCAN. A driver circuit is needed for the physical connection to the bus, where most people use a TI SN65HVD230 CAN Bus module breakout boards that are 3.3V compatible.
- McASPMultichannel Audio Serial Port:
- Multichannel Audio Serial Port (McASP) is connected to the HDMIHigh-Definition Multimedia Interface framer that can be used to interface to McASP-capable audio codecs (e.g., the TITexas Instruments TLV320AIC series). Audio data is transferred between the TLV320AIC and the McASP0 of the AM335x via the audio serial bus interface. This interface can be configured to support different modes of operation including the I2SInter-IC Sound protocols or TDMTime-Division Multiplexed stream.
- MMCMultimedia Card:
- The MMC are interface buses that are used to connect the microSD card (MMC0) and eMMCEmbedded Multimedia Card (MMC1) to the processor. MMC1 has 10 pins to connect to the processor that also connect to the P8 expansion connector. When MMC1 is used for other functions, the eMMC cannot be used, which means you must boot from the microSD slot.
- LCDLiquid Crystal Display:
- A single HDMI interface is connected to the 16-bit LCD interface on the processor. The 16-bit interface was used to preserve as many expansion pins as possible to allow for use by the user. The HDMI Framer IC is used to convert the LCD interface to HDMI and convert the audio as well. The signals are still connected to the expansion headers to enable the use of LCD expansion boards (e.g., LCD capes) or access to other functions on the board as needed.
- GPMCGeneral Purpose Memory Controller:
- The General-Purpose Memory Controller (GPMC) is used to connect to external memory devices like FPGAField-Programmable Gate Arrays or ASICAplication-Specific Integrated Circuits. The GPMC bus conflicts with the eMMCEmbedded Multimedia Card on the board, so it may will not be available due to the use of those signals by the eMMC. If the eMMC is used for booting only and the file system is on the microSDThe microSD is a Secure Digital (SD) removable miniaturized flash memory card that is the compact version of a standard SD card and is meant to be used with smaller devices. card, then these signals could be used.
- Power & Reset Button Pins:
-
- The PWR_BUT pin (Header P9 on Pin9) is a 5V level as pulled up internally by the PMIC. It is activated by pulling the signal to GND. This can be used to alert the processor to initiate the power down sequence.
- SYS_RESETn (Header P9 on Pin10) pin can act as an input or an output. When the reset button is pressed, it sends a reset signal to the processor and to the system.
The BeagleBone Black has the ability to accept up to four expansion boards or capes that can be stacked onto the expansion headers. The word cape comes from the shape of the board as it is fitted around the Ethernet connector on the main board. This notch acts as a key to ensure proper orientation of the cape.
There are different ways of accessing and controlling the GPIO pins through software. The most popular approach is using Python with the Adafruit_BBB Library. You can also control the pins with the Linux file system (sysfs) by writing commands in the terminal or using a shell script. BoneScript is a JavaScript library on the Beagle boards using the Node.js interpreter that can also be used to read/write to the GPIO.
User I/O
The board has user I/OInput/Output that includes buttons as a means of controlling the processor and LEDLight Emitting Diodes to check the status of board.
Status LEDs
There are a total of five blue LEDs on the board. One is the power LED and the other 4 LEDs can be controlled via software by setting GPIO pins. While the four user LEDs can be overwritten and used as desired, they do have specific meanings in the image that is shipped with the board once the Linux kernel has booted.
- USER0:
- is the heartbeat indicator from the Linux kernel
- USER1:
- turns on when the microSD card is being accessed
- USER2:
- is an activity indicator that turns on when the kernel is not in the idle loop
- USER3:
- turns on when the onboard eMMC is being accessed
There are also two LEDs on the RJ45RJ45 is the most common type of the connector used for Ethernet networking. RJ stands for “Registered Jack” and 45 refers to the interface standard number. It has eight pins, which means that it contains eight separate wires. connector to provide Ethernet status indication. One is yellow (100M Link up if on) and the other is green (Indicating traffic when flashing).
Power
A minimum power supply of 5V 1A DC can be used to power the board by itself and a 5V 2A DC supply is recommended if powering external devices from the board. The power supply current depends on how many and what type of I/O devices and add-on boards are powered by the board. If heavier use of the GPIO or USB host port is expected, then a higher current supply will be required.
The board can be powered through four different inputs:
- Barrel Jack
- Mini USB
- GPIO
- Battery Pins
The TPS65217C PMICPower Management Integrated Circuit (PMIC) is used along with a separate LDOLow Dropout Regulator (LDOTLV70233) to provide power to the system. The PMIC consist of a linear dual-input power path, three step-down converters, and four LDOs. The PMIC and external LDO provides the power rails to the various components on the board, producing different voltage levels to components and output pins. For example, the processor uses 1.8V, the DDR3L SDRAM requires 1.5V, and on the GPIO there is there is a 5V output, a 3.3V output, and a 1.8V reference for the analog-to-digital converters. The PMIC LDOs produces 1.5V and 1.8V, while external LDOTLV70233 provides the 3.3V rail for the rest of the board.
The selection of the barrel jack or the mini USB as the power source is handled internally by the PMIC and automatically switches to barrel jack power if both are connected. The power configuration can be changed in software using the I2C interface from the processor and it can also read the PMIC to determine if the board is running on the barrel jack input or the USB input.
The PMIC can be used to shut down the board correctly by using a "soft" shutdown from the OSOperating System or by pressing the power button once. A "hard" power down can be performed by holding the power button down for about eight seconds. You generally should not shut the power down by pulling the power supply plugs for the barrel jack or mini USB, but if you need to then hold the reset button while doing so to lower system power usage.
Barrel Jack
The primary way to power the board is using the barrel jack on the top of the board. The barrel plug has the following requirements:
- Operating voltage must be 5V with a current rating of 1A to 2A
- Center positive (the middle pin of the plug has to be positive)
- Inside diameter (ID) of 2.1mm
- Outside diameter (OD) of 5.5mm
- Connector length of 9.5mm or greater is sufficient
The barrel jack is preferred over the mini USB as a power source because it can provide more current to the board for powering external devices. By default, the mini USB port is limited to 500mA by the PMIC.
Mini USB
The mini USB port on the bottom of the board can be used to power the board and as a client for tethering to a PC. The board comes with a 3ft USB-A to Mini-B USB Cable for this purpose.
The mini USB port is limited to 500mA by the PMIC. It is possible to change the settings in the PMIC to increase this current, but only after the initial boot, and at that point the PC most likely will complain, but you can also use a dual connector USB cable to the PC to get to 1A. In some instances, the PC may not be able to supply sufficient power for the board (a typical USB port on a PC is limited to 500mA max), in which case an external power supply to the barrel jack can be used.
When powering from the USB port, the VDD_5V rail is not provided to the GPIO, so capes that require the 5V rail to supply the cape direct, bypassing the PMIC, will not have that rail available for use. The 5V DC supply from the USB port is provided on the SYS_5V rail of the GPIO header for use by a cape.
GPIO
Power routed to the board by the VDD_5V GPIO header pin could be provided directly or from power derived on a cape. The power supply should be a well regulated 5V±0.25V DC.
The VDD_5V pins (Header P9, Pins 5 and 6) are directly tied to the barrel jack, so you should not power both inputs at the same time.
The GPIO SYS_5V pins (Header P9, Pins 7 and 8) comes from the mini USB and should only be used as output power for devices (limited to 250mA).
The VDD_3V3B pins (Header P9, Pins 3 and 4) are supplied by the LDOLow Dropout Regulator on the board and is the primary output power rail for expansion boards.
Battery
The PMICPower Management Integrated Circuit (PMIC) has built-in battery charging capability. Four pin through holes are provided on the board to allow access to the battery pins on the PMIC. A 2x2 header can be soldered to the holes or you may just wire a battery directly to the holes. The four pins are defined in the table below.
| Pin | Function |
|---|---|
| BAT (TP5) | Battery connection point |
| SENSE (TP6) | Battery voltage sense input, connect BAT directly at the battery terminal. |
| TS (TP7) | Temperature sense input. Connect to NTC thermistor to sense battery temperature. |
| GND (TP8) | System ground |
The PMICPower Management Integrated Circuit (PMIC) can operate at a lower supply than 5V, allowing a singe 3.7V cell to be used to power the entire board (there is no need to step-up to 5V or to run dual cells and step-down to 5V). Any Lithium Ion (Li-Ion) or Lithium Polymer (LiPo) single cell can be used, preferably with a built-in protection circuit.
Choosing the appropriate battery capacity depends on how long the board needs to be powered from the battery and what peripherals are consuming power. The board consumes around 300mA to 500mA by itself, so cell of 700mA would give over an hour of use and a 2Ah cell will provide several hours of use. Using a battery can also serve as a backup supply in case the main power (from the barrel jack or from the mini USB) gets disconnected.
There is no fuel gauge function provided by the PMICPower Management Integrated Circuit (PMIC). That would need to be added if that function was required. If you want to add a fuel gauge, an option is to use 1-wire SPISerial Peripheral Interface or I2CInter-Integrated Circuit. Also referred to as IIC or I2C. device. You will need to add this using the GPIOGeneral Purpose Input Output expansion headers. More details on using a battery can be found in this element14 post.
Conclusion
This hardware overview of the BBB covered specs, board layout, pinout, processors, memory, I/O, and power. The BBB is an open-source, community-supported embedded computer designed for engineering and industrial applications, with a focus on programmability and customization.
A unique feature of the BBB is the inclusion of 2x PRUProgrammable Real-time Unit 32-bit microcontrollers, where you can achieve fast, deterministic, real-time control of I/O pins and devices without bottlenecking the CPUCentral Processing Unit. It can trigger or receive interrupts, accesses the PWMPulse-Width Modulations, read ADCAnalog-to-Digital Converter (ADC, A/D, or A-to-D)s values, or access the main memory for sharing with the CPU.
Compared to the Raspberry Pi 4B SBC, the BBB is better suited for interfacing external devices in time critical applications, with a more extensive GPIO header and PRU microcontrollers. The Raspberry Pi 4B was designed for general-purpose computing and hobbyist projects, with a focus on ease of use and more powerful processing and memory options.
References
| Category | Reference Description | Links |
|---|---|---|
| Board | beagleboard.org BeagleBone Black Webpage includes links to Documentation, Quick Start Guide, and Software Images | beagleboard.org |
| Processor | TI Sitara AM3358 Processor Product Page includes Specs, Datasheet (PDF), and Technical User Manual (PDF) | ti.com |
| Ethernet | Microchip LN8710A Ethernet Transceiver IC Product Page includes Specs, Datasheet (PDF), and Application Notes | microchip.com |
| HDMI | NXP TDA19988 HDMI Framer IC Datasheet (PDF) | TDA19988 Datasheet |
| PMIC | TI TPS65217C PMIC Product Page includes Specs, Datasheet (PDF), Application Notes, User Guides, and Technical Articles | ti.com |
| GPIO | Adafruit BBIO Python Library guide on controlling the GPIO pins with Python | Adafruit BBIO Guide |
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17Aug2024 09:03:39 UTC
2024-08-17T09:03:39Z
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Raspberry Pi 4B (RPi4B) specs, board layout, components, I/O, and power.
Products
Created:
06Mar2023 19:28:09 UTC
2023-03-06T19:28:09Z
Updated:
03Sep2024 08:04:51 UTC
2024-09-03T08:04:51Z
- Processors:
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- TITexas Instruments AM335x 1GHz ARM® Cortex-A8 CPUCentral Processing Unit
- 2x PRUProgrammable Real-time Unit 32-bit microcontrollers
- PowerVR SGX530 3D GPUGraphics Processing Unit
- Memory:
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- 512MB DDRDouble Data Rate (DDR) is a type of SDRAM memory that fetches data on both the leading edge and the falling edge of the clock signal that regulates it.3 RAMRandom Access Memory
- 4GB 8-bit eMMCEmbedded Multimedia Card on-board flash storage
- microSDThe microSD is a Secure Digital (SD) removable miniaturized flash memory card that is the compact version of a standard SD card and is meant to be used with smaller devices. card slot for loading operating system and data storage
- Connectivity:
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- 1x USB 2.0 port, 1x microHDMI port, and 1x 10/100 RJ45RJ45 is the most common type of the connector used for Ethernet networking. RJ stands for “Registered Jack” and 45 refers to the interface standard number. It has eight pins, which means that it contains eight separate wires. Ethernet port
- 2x 46-pin GPIOGeneral Purpose Input Output headers
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