180
Am79C976
8/01/00
P R E L I M I N A R Y
6
EXDINTE
Obsolete function. Writing has no
effect. Read as undefined.
5
MPPLBA
Magic Packet Physical Logical
Broadcast Accept. If MPPLBA is
at its default value of 0, the
Am79C976 controller will only de-
tect a Magic Packet frame if the
destination address of the packet
matches the content of the physi-
cal address register (PADR). If
MPPLBA is set to 1, the destina-
tion address of the Magic Packet
frame can be unicast, multicast,
or broadcast. Note that the set-
ting of MPPLBA only affects the
address detection of the Magic
Packet frame. The Magic Packet
frame
’
s data sequence must be
made up of 16 consecutive phys-
ical addresses (PADR[47:0]) re-
gardless
of
what
destination address it has. This
bit is OR
’
ed with EMPPLBA bit
(CSR116, bit 6).
kind
of
Read/Write accessible. MPPLBA
is set to 0 by H_RESET or
S_RESET and is not affected by
setting the STOP bit.
4
MPINT
Magic Packet Interrupt. Magic
Packet Interrupt is set by the
Am79C976 controller when the
device is in the Magic Packet
mode and the Am79C976 con-
troller receives a Magic Packet
frame. When MPINT is set to 1,
INTA is asserted if IENA (CSR0,
bit 6) and the enable bit MPINTE
are set to 1.
Read/Write accessible. MPINT is
cleared by the host by writing a 1.
Writing a 0 has no affect. MPINT
is
cleared
by
S_RESET, or by setting the
STOP bit.
H_RESET,
3
MPINTE
Magic Packet Interrupt Enable. If
MPINTE is set to 1, the MPINT bit
will be able to set the INTR bit.
Read/Write accessible. MPINTE
is cleared to 0 by H_RESET or
S_RESET and is not affected by
setting the STOP bit.
2
MPEN
Magic Packet Enable. MPEN al-
lows activation of the Magic
Packet mode by the host. The
Am79C976 controller will enter
the Magic Packet mode when
both MPEN and MPMODE are
set to 1.
Read/Write accessible. MPEN is
cleared to 0 by H_RESET or
S_RESET and is not affected by
setting the STOP bit.
1
MPMODE
The Am79C976 controller will en-
ter the Magic Packet mode when
MPMODE is set to 1 and either
PG is asserted or MPEN is set
to 1.
Read/Write
MODE is cleared to 0 by
H_RESET or S_RESET and is
not affected by setting the STOP
bit.
accessible.
MP-
0
SPND
Suspend. Setting SPND to 1 will
cause the Am79C976 controller
to start requesting entrance into
suspend mode. The host must
poll SPND until it reads back 1 to
determine that the Am79C976
controller has entered the sus-
pend mode. Setting SPND to 0
will get the Am79C976 controller
out of suspend mode. SPND can
only be set to 1 if STOP (CSR0,
bit 2) is set to 0. H_RESET,
S_RESET or setting the STOP bit
will get the Am79C976 controller
out of suspend mode.
Requesting entrance into the
suspend mode by the host de-
pends on the setting of the
FASTSPNDE bit (CSR7, bit 15).
Refer to the bit description of the
FASTSPNDE bit and the Sus-
pend section in
Detailed Func-
tions, Buffer Management Unit
for details.
In suspend mode, all of the CSR
and BCR registers are accessi-
ble. As long as the Am79C976
controller is not reset while in
suspend mode (by H_RESET,
S_RESET or by setting the STOP
bit), no re-initialization of the de-
vice is required after the device