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.
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 MDIO protocol?
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 RMII?
Reduced media-independent interface (RMII) is a standard which was developed to reduce the number of signals required to connect a PHY to a MAC.
What does Mdio mean?
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.
What is PHY register?
PHY registers are accessed via packets on a serial management bus known as MDIO, SMI or MIIM, depending on who you ask. The original packet format on this bus as defined by Clause 22 of IEEE 803.3 supports access to up to 32 registers on 32 different PHY addresses.
How do you set up a PHY address?
In many devices, there are ways to set the PHY address through the PHYAD pins. However, there are usually a max of 3 bits to determine the address uniquely. If a PHY Address of 9 (01001) can be chosen, it can contend with a device with a PHY Address of 1 (00001) as the upper 2 bits are configurable only by register.
What is SGMII and RGMII?
Reduced gigabit media-independent interface (RGMII) Serial media-independent interface (SMII) Serial gigabit media-independent interface (serial GMII, SGMII) High serial gigabit media-independent interface (HSGMII)
What is a PHY?
A PHY, an abbreviation for “physical layer”, is an electronic circuit, usually implemented as an integrated circuit, required to implement physical layer functions of the OSI model in a network interface controller.
How many data frames are in I2C?
Characteristics
| Wires | 2 (SCL and SDA) |
|---|---|
| Data Frame Size | 8 Bits packets |
| Maximum speed | Standard mode = 100 Kbps |
| Fast Mode = 400 Kbps | |
| High-Speed mode = 3.4 Mbps |
What is Mdio used for?
What is MDIO interface?
The MDIO Interface component supports the Management Data Input/Output, which is a serial bus defined for the Ethernet family of IEEE 802.3 standards for the Media Independent Interface (MII). The MII connects Media Access Control (MAC) devices with Ethernet physical layer (PHY) circuits.
What is SGMII used for?
The Serial Gigabit Media Independent Interface (SGMII) is a connection bus for Ethernet Media Access Controllers (MACs) and Physical Layer Devices (PHYs) defined by Cisco Systems. It replaces the classic 22-wire GMII connection with a low pin count, 4-pair, differential SGMII connection.
What is the basic frame format of MDIO?
Clause 22 defines the MDIO communication basic frame format (figure 13) which is composed of the following elements: Figure 13: Basic MDIO Frame Format The frame format only allows a 5-bit number for both the PHY address and the register address, which limits the number of MMDs that the STA can interface.
What are the limitations of the MDC frame format?
MDC is specified to have a frequency of up to 2.5 MHz. The frame format only allows a 5-bit number for both the PHY address and the register address, which limits the number of MMDs that the STA can interface. Additionally, Clause 22 MDIO only supports 5V tolerant devices and does not have a low voltage option.
How many registers can a single MDIO interface access?
In the original specification, a single MDIO interface is able to access up to 32 registers in 32 different PHY devices. These registers provide status and control information such as: link status, speed ability and selection, power down for low power consumption, duplex mode (full or half), auto-negotiation, fault signaling, and loopback.
What are the signals on the MDIO bus?
The MDIO bus has two signals: Management Data Clock (MDC) and Managment Data Input/Ouput (MDIO). MDIO has specific terminology to define the various devices on the bus. The device driving the MDIO bus is identified as the Station Management Entity (STA).