BeagleBoard Architecture & Theory
BeagleBoard and BeagleBone single-board computers leverage high-performance TI Sitara processors (such as the AM335x) containing ARM Cortex-A8 cores paired with dual 32-bit Programmable Real-Time Units (PRUs). Unlike standard computer chips, this hybrid structure allows a full Linux operating system to manage networking and files while the independent PRUs run real-time, deterministic physical control of I/O pins, avoiding standard kernel processing latency.
Tip: Standard BeagleBone pins run on 3.3V logic. Connecting any digital or analog pin directly to a 5V sensor without a logic level shifter will damage the Sitara SoC.
About This Reference Guide
Your direct lookup path for BeagleBoard, BeagleBone, and PocketBeagle systems.
This reference index consolidates pin configurations, expansion header maps, and line assignments for classic BeagleBoard, BeagleBone Black/Blue/Green, and pocket-sized formats.
Finding accurate pin layouts is essential for system integrators, embedded software developers, roboticists, and hardware designers. Correct pin alignments prevent bus conflicts, boot failures, and permanent damage from short-circuits.
Always verify operating voltages (especially the 1.8V ADC limits) before modifying hardware setups. Correct connections ensure system stability and peripheral safety.
Core PlatformsBeagleBoard, xM, BeagleBone, BeagleBone Black, and PocketBeagle.
Robotics FocusBeagleBone Blue featuring onboard motor controllers and IMUs.
IoT ExpansionBeagleBone Green and Green Wireless with built-in Grove ports.
Real-Time ProcessingComprehensive listings of PRU and hardware interrupts.
Frequently Asked Questions
1. What is the difference between the P8 and P9 headers on BeagleBone?
The P8 and P9 headers are twin 46-pin connectors that break out different SoC buses. P8 focuses primarily on digital GPIOs and LCD lines, while P9 contains analog inputs (ADCs), TWI/I2C buses, UARTs, and system power inputs.
2. Why is the BeagleBone analog input limit of 1.8V critical?
The Sitara AM335x ADC pins are designed strictly for a maximum of 1.8V. Exceeding 1.8V on any analog input pin will immediately destroy the internal ADC module, even if the rest of the board survives.
3. What are the PRUs and how are their pins used?
The Sensory System Subsystem PRUs are dual 32-bit RISC microcontrollers running at 200MHz inside the main SoC. They can directly toggle specific pins mapped to the P8/P9 headers with zero delay, bypassing the Linux operating system.
4. How do I enable a serial port or SPI on BeagleBone Black?
BeagleBoard systems use Device Tree Overlays (.dtbo files) to configure pin multiplexing. You must specify and enable the correct overlay in your system config file (/boot/uEnv.txt) before you can use the pins.
5. What makes BeagleBone Blue unique for robotics?
The BeagleBone Blue integrates multiple onboard motor control chips (H-Bridges), quadrature encoder counters, servo outputs, a 9-axis IMU, and a JST battery charge regulator directly onto the main board, eliminating the need for external capes.
6. Can I use standard capes on the BeagleBone Green?
Yes. The BeagleBone Green is physically and electrically compatible with BeagleBone Black cape standards. It replaces the HDMI port with dual Grove sensor ports, so capes that require HDMI output cannot be used.