Table 522: Auto Power Down Register (Address 1Ch, Shadow Value 01010) - Broadcom BCM5722 Programmer's Manual

Programmer's Guide
10/15/07
Link Utilization LED Selector
These bits apply to the LED programmed to the ACTIVITY mode only. In the activity LED mode, the LED expresses an
estimated activity in terms of blink rate. The blink rate of the LED increases as the activity duty cycle increases by increments
of 10%. For duty cycles of 0.001 to10%, the LED blinks at 3 Hz; for duty cycles of 10% to 20%, the LED blinks at 6 Hz; and
for duty cycles of 90% to 96%, the LED blinks at 30 Hz. Even though the frequency of the LED blink increases, the duty cycle
of the LED stays at about 50%. The ACTIVITY LED can be programmed to display the following:
• 00 = Normal activity (fixed blink rate)
01 = Transmit activity with variable blink rate
•
• 10 = Receive activity with variable blink rate
11 = Transmit/receive activity with variable blink rate
•
A P D
UTO OWER OWN

Table 522: Auto Power Down Register (Address 1Ch, Shadow Value 01010)

Bit Field
15 Write Enable
14:10 Shadow Register Selector
9:6 Reserved
5 Auto Power Down Mode
4 Sleep Timer Select
3:0 Wakeup Timer Select
Write Enable
During a write to this register, setting Auto Power Down register bit 15 allows writing to bits [9:0] of this register. For reading
the values of bits [9:0], perform an MDIO write with bit 15 cleared and preferred shadow values in bits [14:10]. The next MDIO
read of register address 1Ch contains the preferred Shadow register values in bits [9:0].
Shadow Register Selector
Register bits [14:10] must be set to 01010 to enable read/write to the Auto Power Down register address 1Ch.
Auto Power-Down Mode Enable
Setting this bit enables the Auto Power-Down Mode.
Sleep Timer Select
Setting this bit changes the wakeup time leaving Auto Power-Down Mode.
Document 5722-PG101-R
(PHY_A = 0 1, R
DDR X
Description
• 1 = Write bits [9:0].
• 0 = Read bits [9:0].
01010 = Auto Power Down register.
Write as 0h, ignore when read.
• 1 = Auto power down mode enabled.
• 0 = Auto power down mode disabled.
• 1 = Sleep timer is 5.4s.
• 0 = Sleep timer is 2.7s.
Counter for Wakeup timer in units of 84 ms.
• 0001 = 84 ms.
• 0010 = 168 ms.
• ...
• 1111 = 1.26s.
Bro adco m Co rp or atio n
_A = 1C , S
EG DDR H
BCM5722
01010 )
HADOW B
Init
0
01010
0h
0
0
0001
Transceiver Registers
Access
R/W
R/W
R/W
R/W
R/W
R/W
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