RM0082
HS_Media independent interface (MII)
Doc ID 018672 Rev 1
543/844
register (1.4.2.25), in addition to the detecting Pause frame with the unique multicast
address.
Clearing this bit, the MAC will detect only a Pause frame with the unique multicast
address specified in the 802.3x standard.
●
RFE
Setting this bit, the MAC will decode the received Pause frame and disable its
transmitter for a specified time (Pause Time). Otherwise (bit cleared), the decode
function of the Pause frame is disabled.
●
TFE
(In Full-Duplex mode) Setting this bit, the MAC enables the flow control operation to
transmit Pause frames. Otherwise (bit cleared), no Pause frames will not be transmitted
by MAC.
(In Half-Duplex mode) Setting this bit, the MAC enables the back-pressure operation.
Otherwise (bit cleared), back-pressure feature is disabled.
●
FCB/BPA
Setting this bit, a Pause Control frame is initiated in Full-Duplex mode and the back-
pressure function is activated in Half-Duplex mode (if TFE bit above is set).
Note:
(In Full-Duplex mode) During a transfer of the Control Frame, this bit will continue to be set
meaning that a frame transmission is in progress. After the completion of Pause control
frame transmission, the MAC will clear this bit.
24.7.23 VLAN
tag
register (Register7, MAC)
The VLAN tag is a register which contains the IEEE 802.1Q VLAN tag to identify the VLAN
frames. The MAC compares the 13
th
and the 14
th
bytes of the receiving frames (length/type)
with 0x8100, and the following 15
th
and 16
th
bytes with the VLAN tag: if a match occurs, the
MAC sets the VLAN bit in the received frame status word (receive descriptor 0, ). The GMII
data bit assignments are given in
.
24.7.24
Wake-up frame filter register (Register10, MAC)
This register is actually a 32 bit pointer used by the application to access (read/write) eight
(not transparent) Wake-up Frame Filter registers, reported in
, involved in the
power management (PMT, see
It means that eight sequential Write operations to this address will write all wake-up frame
filter registers, and eight sequential read operations from this address will read all Wake-up
Frame Filter registers.
Table 453.
VLAN tag register bit assignments
Bit
Name
Reset
value
Type
Description
[31:16]
Reserved
-
RO
Read: undefined.
[15:00]
VL
16’h0
RW
VLAN tag identifier.