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Embedded Tri-Mode Ethernet MAC User Guide
79
UG074 (v2.2) February 22, 2010
Host Interface
R
shows the write timing for the configuration registers through the
management interface. When accessing the configuration registers (i.e., when
HOSTADDR[9] =
1
and HOSTMIIMSEL =
0
), the upper bit of HOSTOPCODE functions as
an active Low write-enable signal. The lower HOSTOPCODE bit (bit[0]) is a “don’t care.”
Table 3-14:
Management Configuration Register
MSB
LSB
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10
9
8
7
6
5
4
3
2
1
0
0x340
RESERVED
MD
IOE
N
CLOCK_DIVIDE[5:0]
Bit
Description
Default Value
R/W
[5:0]
Clock divide [5:0]: This value is used to derive the
EMAC#PHYMCLKOUT for external devices.
See
.
All
0
s
R/W
[6]
MDIO enable: When this bit is
1
, the MDIO interface is used to
access the PHY. When this bit is
0
, the MDIO interface is
disabled, and the MDIO signals remain inactive.
See
.
TIEEMAC#CONFIGVEC[73]
R/W
[31:7]
Reserved.
–
Figure 3-40:
Configuration Register Write Timing
HO
S
TCLK
HO
S
TADDR[8:0]
HO
S
TADDR[9]
HO
S
TOPCODE[1]
HO
S
TMIIM
S
EL
HO
S
TWRDATA[31:0]
u
g074_3_42_080805
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