ENC28J60/SS

DescriptionENC28J60 is an independent Ethernet controller with industry standard Serial Peripheral Interface (SPI). It is designed as an Ethernet network interface for any controller equipped with SPI. ENC28J60 meets all IEEE 802.3 specifications. It integrates multiple packet filtering schemes to restrict incoming packets. It also provides an internal DMA module for fast data throughput and hardware assisted checksum calculation, which is widely used in network protocols. Communication with the host controller is achieved through interrupt pins and SPI, with a clock rate of up to 20 MHz. Two dedicated pins are used for LED linking and network activity indication. Figure 1-1 shows a simple block diagram of ENC28J60. Figure 1-2 shows a typical application circuit using the device. With the ENC28J60, only two pulse transformers and some passive components are needed to connect the microcontroller to the Ethernet network. ENC28J60 includes seven main functional modules: 1 The SPI interface serves as the communication channel between the host controller and ENC28J60. 2. Control registers used for controlling and monitoring ENC28J60. 3. A dual port RAM buffer used for receiving and sending data packets. 4. Arbitrator used to control access when DMA, sending, and receiving modules request access to RAM buffer. 5. Explain the bus interface for receiving data and commands through the SPI interface. 6. Implement a MAC (Media Access Control) module that complies with IEEE 802.3 standard MAC logic. 7. PHY (Physical Layer) module that encodes and decodes analog data present on twisted pair interfaces. The device also includes other supporting modules such as oscillators, on-chip voltage regulators, and level converters to provide 5V withstand voltage I/O and system control logic.