## Overview of the NET2280EVB The **NET2280EVB** is an evaluation board designed for the **NET2280**, a PCI to USB 2.0 Peripheral Controller. This board allows developers to prototype and test high-speed USB peripheral designs by interfacing them with a standard PCI bus. --- ### Core Electronic Components The board is composed of several critical subsystems that manage data translation, power regulation, and connectivity. | Component Category | Key Parts / Description | Function | | :--- | :--- | :--- | | **Main Controller** | PLX Technology NET2280 | The heart of the board; manages USB 2.0 high-speed protocol and PCI target operations. | | **USB Interface** | USB Type-B Connector | Provides the physical connection to the USB Host (PC). | | **PCI Interface** | 32-bit/33MHz PCI Edge Connector | Connects the evaluation board to a motherboard or backplane. | | **EEPROM/Flash** | 93C46 or equivalent | Stores configuration data and Vendor/Product IDs for the NET2280. | | **Clock Source** | 30MHz Crystal Oscillator | Provides the timing reference for the USB PHY and internal logic. | | **Voltage Regulation** | LDO Regulators (3.3V / 1.8V) | Steps down power to provide clean voltage to the digital core and I/O. | --- ### Key Technical Specifications * **USB Support:** USB 2.0 High-Speed (480 Mbps) and Full-Speed (12 Mbps). * **PCI Support:** 32-bit, 33MHz, PCI v2.2 compliant. * **Endpoints:** Supports up to 4 configurable endpoints for data transfer. * **FIFO:** Integrated 8KB FIFO for buffering data between the USB and PCI buses. * **DMA Controller:** Includes an internal DMA engine to offload data transfers from the local CPU. --- ### Functional Block Layout 1. **PCI Target Interface:** Logic that allows the NET2280 to appear as a standard PCI device to the host system. 2. **USB Transceiver (PHY):** An integrated physical layer that handles the differential signaling (D+/D-) for USB communication. 3. **Local Bus Interface:** While the NET2280 is primarily a PCI device, the EVB often includes headers to monitor the local bus signals for debugging. 4. **Status LEDs:** Typically includes power indicators and USB activity lights to provide visual feedback during firmware development. --- ### Use Cases for the EVB * **Driver Development:** Writing Windows/Linux drivers for custom USB hardware. * **Firmware Testing:** Validating USB descriptors and endpoint configurations. * **Legacy Porting:** Converting older PCI-based hardware designs to be accessible via USB.