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. The management of these PHYs is based on the access and modification of their various registers.

What is Mii in Linux?

On Linux operating systems, the mii-tool utility checks or sets the status of a network interface’s MII (Media Independent Interface) unit. Many Ethernet adapters use an MII to autonegotiate link speed and duplex setting.

What is Phy address?

The PHY address is latched into the device at power up or hardware reset, and is hard coded in the software. The PHY addresses are written into shared data RAM with the offset defined as follows, to notify PRU firmware.

Is MDIO the 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.

How do I use MII tool on Linux?

Make sure that your NIC should support mii-tool.

1. 1) Mii Tool (default output) By default mii-tool shows below results on the console.
2. 2) Force set speed.
3. 3) Initiate auto-negotiation.
4. 4) Set to Full Duplex.
5. Conclusion.

Is MDIO a 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. MDIO works with 1.2V supply with a clock rate of 4MHz (downward compatibility to 100 kHz).

Does MDC need pull up?

MDC is an output. Basically, it does not need a pull-up.

Is MDC open drain?

MDIO is open drain.

What is MDC in Ethernet?

The IEEE 802.3 Ethernet Standard defines a medium independent interface for all speeds ranging from 10 MBit/s to 10GBit/s. The MDIO interface clock (MDC) speed is defined for up to 2.5 MHz.

How do internal pull-up resistors work?

With a pull-up resistor, the input pin will read a high state when the button is not pressed. In other words, a small amount of current is flowing between VCC and the input pin (not to ground), thus the input pin reads close to VCC. When the button is pressed, it connects the input pin directly to ground.

What is the use of MDIO interface in Ethernet?

A Data interface to the Ethernet MAC, for sending and receiving Ethernet frame data. 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.

What does MDIO stand for?

Management Data Input/Output (MDIO), also known as Serial Management Interface (SMI) or Media Independent Interface Management (MIIM), is a serial bus defined for the Ethernet family of IEEE 802.3 standards for the Media Independent Interface, or MII. The MII connects Media Access Control (MAC) devices with Ethernet physical layer (PHY) circuits.

What pull-up resistor do I need for an MDIO device?

The MDIO requires a specific pull-up resistor of 1.5 kΩ to 10 kΩ, taking into account the total worst-case leakage current of 32 PHYs and one MAC. Before a register access, PHY devices generally require a preamble of 32 ones to be sent by the MAC on the MDIO line.

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.