Is MDIO same as I2C?
MDIO – A short history For most pluggable optical transceivers the interface used for monitor and control is the I2C interface. Defined as part of MII in IEEE802. 3 clause45, MDIO can also be used in high speed optical transceivers like CFP, CFP2 or CFP4 instead of 100 Megabit.
What is MDC and MDIO?
Electrical specification The MDIO interface is implemented by two signals: MDIO Interface Clock (MDC): clock driven by the MAC device to the PHY. MDIO data: bidirectional, the PHY drives it to provide register data at the end of a read operation.
What is MDIO used for?
Management Data Input/Output, or MDIO, is a 2-wire serial bus that is used to manage PHYs or physical layer devices in media access controllers (MACs) in Gigabit Ethernet equipment.
Is MDIO open drain?
MDIO is open drain. Like you mentioned, during idle the line will go high to VDD. The level shifter above is a good choice.
What is a PHY transceiver?
Ethernet physical transceiver The Ethernet PHY is a component that operates at the physical layer of the OSI network model. It implements the physical layer portion of the Ethernet. Its purpose is to provide analog signal physical access to the link.
What is PHY device?
An Ethernet PHY is designed to provide error-free transmission over a variety of media to reach distances that exceed 100m. The Ethernet PHY is connected to a media access controller (MAC). The MAC is usually integrated into a processor, FPGA or ASIC and controls the data-link-layer portion of the OSI model.
What is SDA and SCL in I2C?
I2C bus wires are called SDA (Serial DAta line) and SCL (Serial CLock line). They are both bi-directional and assure the communication between the network devices through the SDA and SCL signals (Fig. 11).
Why PHY is used in Ethernet?
What is PHY and PHY?
A PHY connects a link layer device (often called MAC as an acronym for medium access control) to a physical medium such as an optical fiber or copper cable. A PHY device typically includes both physical coding sublayer (PCS) and physical medium dependent (PMD) layer functionality.
What is a MAC vs PHY?
The PHY layer defines the physical and electrical characteristics of the network. It is responsible for managing the hardware that modulates and demodulates the RF bits. The MAC layer is responsible for sending and receiving RF frames.
How does SDA and SCL work?
SCL is the clock line. It is used to synchronize all data transfers over the I2C bus. SDA is the data line. The SCL & SDA lines are connected to all devices on the I2C bus.
What is ACK and NACK in I2C?
Ack/Nack. The I2C protocol specifies that every byte sent must be acknowledged by the receiver. This is implemented with a single bit: 0 for ACK and 1 for NACK. At the end of every byte, the transmitter releases the SDA line, and on the next clock cycle the receiver must pull the line low to acklowledged the byte.
What is MII and RGMII?
The MII was standardised a long time ago and supports 100Mbit/sec speeds. A version using less pins is also available, RMII (‘R’ for reduced). For gigabit speeds, the GMII (‘G’ for gigabit) interface is used, with a reduced pincount version called RGMII.
What is the difference between MDIO and MDC?
MDIO data: bidirectional, the PHY drives it to provide register data at the end of a read operation. The bus only supports a single MAC as the master, and can have up to 32 PHY slaves. The MDC can be periodic, with a minimum period of 400 ns, which corresponds to a maximum frequency of 2.5 MHz. Newer chips, however, allow faster accesses.
What is the use of MDIO interface in a PHY?
A PHY management interface, MDIO, used to read and write the control and status registers of the PHY in order to configure each PHY before operation, and to monitor link status during operation. The MDIO interface is implemented by two signals: MDIO Interface Clock (MDC): clock driven by the MAC device to the PHY.
What is a I2C interface?
A I2C Interface consists of just of 2 wires (Clock (SCL) and DATA (SDA)). It works (for optical transceivers) with a clock rate of 1KHz (Standard Mode) or 4KHz (Fast Mode). I2C supports full internal operation for DDM / Digital Diagnostic Monitoring data and uses a 7 or 10 bit adress space. DDM / Digital Diagnostic Monitoring – What is this?
What are the two signal interfaces of the Mii interface?
MII has two signal interfaces: 1 A Data interface to the Ethernet MAC, for sending and receiving Ethernet frame data. 2 A PHY management interface, MDIO, used to read and write the control and status registers of the PHY in order to… More