4 phy acknowledge status register (alive), Section 4.4 – Texas Instruments TMS320C645x DSP User Manual

Page 69

Advertising
background image

www.ti.com

4.4

PHY Acknowledge Status Register (ALIVE)

MDIO Registers

The PHY acknowledge status register (ALIVE) is shown in

Figure 18

and described in

Table 17

.

Figure 18. PHY Acknowledge Status Register (ALIVE)

31

16

ALIVE

R/WC-0

15

0

ALIVE

R/WC-0

LEGEND: R/W = Read/Write; R/WC = Read/Write 1 to clear; -n = value after reset

Table 17. PHY Acknowledge Status Register (ALIVE) Field Descriptions

Bit

Field

Value

Description

31-0

ALIVE

MDIO Alive bits. Each of the 32 bits of this register is set if the most recent access to the PHY with
address corresponding to the register bit number was acknowledged by the PHY; the bit is reset if
the PHY fails to acknowledge the access. Both the user and polling accesses to a PHY will cause
the corresponding alive bit to be updated. The alive bits are only meant to be used to give an
indication of the presence or not of a PHY with the corresponding address. Writing a 1 to any bit
will clear it, writing a 0 has no effect.

0

The PHY fails to acknowledge the access

1

The most recent access to the PHY with an address corresponding to the register bit number was
acknowledged by the PHY.

SPRU975B – August 2006

Ethernet Media Access Controller (EMAC)/Management Data Input/Output (MDIO)

69

Submit Documentation Feedback

Advertising