82801FB Datasheet, PDF (314/786 Pages) Intel Corporation – Intel I/O Controller Hub 6 (ICH6) Family

LAN Controller Registers (B1:D8:F0)
8.3.8
HEART_TIM—Heartbeat Timer Register
(ASF Controller—B1:D8:F0)
Offset Address: E9h
Default Value: 02h
Attribute:
Size:
R/W
8 bits
The HeartBeat Timer register implements the heartbeat timer. This defines the period of the
heartbeats packets. It contains a down counting value when enabled and the time-out value when
the counter is disabled. The timer can be configured and enabled in a single write.
Note: The heartbeat timer controls the heartbeat status packet frequency. The timer is free-running and
the configured time is only valid from one heartbeat to the next. When enabled by software, the
next heartbeat may occur in any amount of time less than the configured time.
.
Bit
Description
Heartbeat Timer Value (HBT_VAL) — R/W. Heartbeat timer load value in 10.7-second resolution.
7:1
This field can only be written while the timer is disabled. (10.7 sec – 23 min range). Read as load
value when HBT_ENA=0. Read as decrementing value when HBT_ENA=1. Timer resolution is
10.7 seconds. A value of 00h is invalid.
Timer Enable (HBT_ENA) — R/W.
0 _{0 = Disable}
1 = Enable / Reset Counter
8.3.9
RETRAN_INT—Retransmission Interval Register
(ASF Controller—B1:D8:F0)
Offset Address: EAh
Default Value: 02h
Attribute:
Size:
R/W
8 bits
This register implements the retransmission timer. This is the time between packet transmissions
for multiple packets due to a SOS.
Bit
Description
Retransmit Timer Value (RTM_VAL) — R/W. Retransmit timer load value 2.7 second resolution.
7:1
This field is always writable (2.7 sec – 5.7 min range). Timer is accurate to +0 seconds, –
0.336 seconds. Reads always show the load value (decrement value never shown). A value of 00h
is invalid.
0 Reserved
314
Intel^® I/O Controller Hub 6 (ICH6) Family Datasheet