EP-0234

Description

The new Raspberry Pi Expansion Board is designed to enhance the functionality of your Raspberry Pi devices with additional interfaces and features. It is tailored for high-density Raspberry Pi clusters and offers a compact solution for advanced projects.

Features

• Dual Front Grove Interfaces:The board features two Grove interfaces on the front for easy access. One interface supports I2C protocol, and the other supports UART protocol.
• Standard Grove Compatibility: Both the I2C and UART interfaces are compatible with standard Grove modules, ensuring a wide range of expandability.
• UID Indicator Light: A front-mounted red LED serves as a UID indicator, using GPIO4, which illuminates with a high logic level for clear status indication.
• I2C and UART Standards: The interfaces are designed to be compatible with standard Grove I2C and Grove UART modules.
• 3.3V Grove Interface Level: Ensures compatibility with a broad range of Grove sensors and modules that operate at 3.3V.
• Raspberry Pi Compatibility: The board is compatible with Raspberry Pi 3B/3B+, Raspberry Pi 4B, and Raspberry Pi 5, providing flexibility for various Raspberry Pi models.
• PCIe NVMe Support: Exclusively on Raspberry Pi 5, the board supports the PCIe NVMe functionality for high-speed data storage options.
• Front Power Input: Offers a USB-C interface for front power input, making it convenient for power supply in dense cluster setups.
• Application Scenarios: Ideal for high-density Raspberry Pi clusters where space and accessibility are crucial.

Specification

Parameter	Value
Grove Interfaces	2 (1x I2C, 1x UART)
Indicator Light	Red UID LED on GPIO4
Logic Level	3.3V
Compatible Models	Raspberry Pi 3B/3B+, Raspberry Pi 4B, Raspberry Pi 5
Special Feature Support	PCIe NVMe on Raspberry Pi 5
Power Input	USB-C front power input 5.1V/5A
Use Case	High-density Raspberry Pi cluster environments

• Pinout and Interface Details

Parameter	Value
Grove I2C	Standard 4-pin Grove connector
Grove UART	Standard 4-pin Grove connector with UART functionality
UID LED	GPIO4 controlled, Red LED
Power Input	USB-C 5V@5A Max
Voltage Level	3.3V for Grove interfaces

Compatibility and Usage

• Ensure that your Raspberry Pi model is compatible with the expansion board.
• Connect Grove sensors and modules to the I2C or UART interfaces depending on their specifications.
• Use the front power input via USB-C for power supply in cluster setups.
• The UID LED can be programmed to indicate various statuses or for identification purposes.

Getting Started

Hardware Assembly

• Attach the expansion board to your Raspberry Pi, ensuring correct alignment.

Power Supply

• Connect power to the USB-C front power input.

Software Configuration

• Configure the Raspberry Pi's software to recognize the new interfaces and GPIO controls.

 We base our instructions on the assumption that you are utilizing Raspberry Pi OS, available in both 64-bit and 32-bit architectures. For the purpose of this guide, we will proceed with Raspberry Pi OS 64-bit, specifically the Bookworm edition, as our reference example.This version provides a clearer and more formal explanation, suitable for a user manual or technical documentation.

For Raspberry Pi 5 Only

Following Steps are for Raspberry Pi 5 Only

• Modify /boot/firmware/config.txt file and adding following parameter:

dtparam=pciex1
dtparam=pciex1_gen=3  # optional  

• Save it and reboot your Raspberry Pi 5.

How to identify your Raspberry Pi by using UID LED indicator

• The UID LED can be programmed to indicate various statuses or for identification purposes.

Module Connection

• Connect your Grove modules to the appropriate interfaces.

Testing

• Test the functionality of the board with sample programs or sensors.