The Gravity: I/O Expansion Shield for Pyboard (SKU: DFR0577) is a versatile expansion shield specifically designed for the Pyboard v1.1 microcontroller. It aims to simplify the process of connecting various sensors and electronic modules, particularly those from the Gravity Series, by offering a plug-and-play solution that eliminates the need for complex wiring and soldering. This design facilitates rapid prototyping and quicker integration of components.
Function Description:
The primary function of this expansion shield is to extend the I/O capabilities of the Pyboard v1.1, making it easier to interface with a wide range of peripherals. It provides numerous dedicated ports for digital, analog, serial (UART), and I2C communication, all configured for the Gravity Series standard connectors. This standardization allows users to quickly connect compatible modules without worrying about pin assignments or voltage levels.
A key feature is its ability to drive high-current components like motors and servos. This is achieved through an external power supply port and a dedicated 3.3V/VIN power switch. Users can select between 3.3V or the external VIN voltage for the X1-X4 ports, which are specifically designed for high-current applications. The remaining ports are powered at a consistent 3.3V.
The shield also integrates an onboard 3.3V LDO (Low-Dropout Regulator) capable of supplying up to 500mA, ensuring stable power for multiple connected modules simultaneously. For user convenience, it includes onboard RST (Reset) and USR (User) buttons, mirroring those on the Pyboard, allowing for easy reset or restoration of the motherboard without direct access to the Pyboard itself.
Important Technical Specifications:
- External Power Supply Voltage: 5V to 12V
- External Power Input Current: <1A
- Connector Type: Gravity series standard connector
- Ports:
- 12 sets of digital ports (Pin: Y3~Y10, Y1, Y2 for UART 6)
- 8 sets of analog ports (Pin: X5~X8, X11, X12, Y11, Y12)
- 1 set of serial port (UART 6, Pin: Y1, Y2)
- 2 sets of I2C ports (I2C 1, Pin: X9, X10)
- 4 high-current digital ports (Pin: X1~X4)
- Interface Signal Level: High Level 3.3V, Low Level 0V
- Analog Input Range: 0V to 3.3V (Note: Pyboard works at 3.3V, so 5V analog input is not supported)
- Onboard LDO Output Voltage: 3.3V
- Onboard LDO Output Current: <500mA
- Board Size: 33mm x 42.6mm
Usage Features:
The Gravity: I/O Expansion Shield is designed for ease of use, particularly for beginners and those looking to accelerate their prototyping process.
- Plug-and-Play: The most significant usage feature is its plug-and-play compatibility with Gravity Series sensors and modules. This eliminates the need for breadboards, jumper wires, and complex wiring diagrams, making it straightforward to connect components.
- Simplified Wiring: By providing dedicated, clearly labeled ports for different types of signals (digital, analog, I2C, UART), the shield simplifies the wiring process. Users can quickly identify the correct port for their module, reducing setup time and potential errors.
- High-Current Drive Capability: The inclusion of X1-X4 ports with selectable 3.3V/VIN power supply allows the shield to directly drive high-current components like motors and servos, which often require more power than the Pyboard's GPIO pins can provide. This expands the range of projects that can be undertaken without additional motor driver shields.
- Power Management: The external power supply input (5-12V) and the 3.3V/VIN power switch offer flexible power management. For projects requiring more power, an external supply can be connected, and the switch can direct this power to the high-current ports. For low-power applications, the Pyboard's power can be sufficient.
- Onboard LDO: The integrated 3.3V LDO ensures a stable power supply for multiple modules, preventing voltage drops that can occur when many components draw power from the Pyboard's limited supply.
- Onboard Buttons: The RST and USR buttons on the shield provide convenient access to the Pyboard's reset and user functions, which is particularly useful when the Pyboard is embedded within a larger setup or when its own buttons are difficult to reach.
- Clear Documentation and Examples: The manual provides clear connection diagrams and sample code for common use cases, such as connecting an analog sound sensor or a servo. This makes it easier for users to get started and understand how to interact with different types of modules.
- Software Library Support: DFRobot has developed software libraries for 10 commonly used sensors and modules, further simplifying the programming aspect. These libraries abstract away low-level details, allowing users to focus on their application logic.
- Compatibility Note: It's crucial to note that due to the Pyboard's 3.3V operating voltage, the analog input range is limited to 0-3.3V. This means 5V analog input is not supported, and all signal pins operate within this 0-3.3V range.
- Insertion Direction: When attaching the shield to the Pyboard, users must pay attention to the direction. The wire terminal of the expansion shield should align with the USB port of the Pyboard motherboard to ensure correct connection.
Maintenance Features:
The Gravity: I/O Expansion Shield is designed to be a robust and low-maintenance component, primarily due to its passive nature and focus on simplifying connections.
- No Soldering Required: The plug-and-play design eliminates the need for soldering for basic connections, reducing the risk of damage from improper soldering and making it easier to swap out modules. This also means less maintenance related to cold joints or damaged traces.
- Standardized Connectors: The use of Gravity Series standard connectors ensures reliable physical connections. These connectors are generally durable and designed for repeated insertions and removals, minimizing wear and tear.
- Overcurrent Protection (Implicit): While not explicitly stated as a maintenance feature, the warning about connecting high-current components to X1-X4 with an external power supply and switching to VIN side implies a level of protection for the Pyboard. Failure to do so could damage the Pyboard, highlighting the importance of following the power guidelines to prevent maintenance issues.
- Onboard LDO Stability: The onboard LDO contributes to system stability by providing a regulated 3.3V supply. This helps prevent issues caused by fluctuating voltages, which can lead to erratic sensor readings or module malfunctions, thereby reducing the need for troubleshooting and maintenance.
- Clear Labeling: All ports are clearly labeled, which aids in correct wiring and reduces the chance of misconnections that could potentially damage modules or the shield itself. This clarity simplifies troubleshooting if issues arise.
- Community Support: DFRobot encourages users to visit their forum for questions, advice, or ideas. This community support can be a valuable resource for troubleshooting and finding solutions to any maintenance-related queries.
- Durability: The board's compact size and robust construction (implied by typical DFRobot product quality) suggest it is designed to withstand typical use in prototyping environments.
- No Moving Parts: As a passive expansion board, it has no moving parts, which inherently reduces the likelihood of mechanical failure and the need for periodic maintenance.
In summary, the Gravity: I/O Expansion Shield for Pyboard is an essential accessory for Pyboard v1.1 users, offering a streamlined approach to connecting sensors and modules, robust power management for high-current applications, and user-friendly features that accelerate development and reduce the complexity of embedded projects. Its design prioritizes ease of use and reliability, making it a valuable tool for both beginners and experienced makers.
To Next Page
Need help?
General
