Chapter 11. Ethernet Module
11-17
Programming Model
Table 11-12. describes the X_DES_ACTIVE fields.
11.5.7 MII Management Frame Register (MII_DATA)
The MII_DATA register, Figure 11-10, is used to communicate with the attached MII
compatible PHY device(s), providing read/write access to their MII registers. Performing
a write to the MII_DATA register causes a management frame to be sourced, unless the
MII_SPEED register has been programmed to 0. In the case of writing to MII_DATA when
MII_SPEED = 0, if the MII_SPEED register is then written to a non-zero value, an MII
frame is generated with the data previously written to MII_DATA. This allows MII_DATA
and MII_SPEED to be programmed in either order if MII_SPEED is currently zero.
31
25
24
23
16
Field
—
X_DES_ACTIVE
—
Reset
0000_0000_0000_0000
R/W
Read/Write
15
0
Field
—
Reset
0000_0000_0000_0000
R/W
Read/Write
Addr
MBAR +0x854
Figure 11-9. X_DES_ACTIVE Register
Table 11-12. X_DES_ACTIVE Field Descriptions
Bits
Name
Description
31–25
—
Reserved, should be cleared.
24
X_DES_ACTIVE
Set to one when this register is written, regardless of the value written. Cleared by
the FEC whenever no additional ready descriptors remain in the transmit ring.
23–0
—
Reserved, should be cleared.
31
30
29
28
27
23
22
18
17
16
Field
ST
OP
PA
RA
TA
Reset
Undefined
R/W
Read/Write
15
0
Field
DATA
Reset
Undefined
R/W
Read/Write
Addr
MBAR + 0x880
Figure 11-10. MII Management Frame Register (MII_DATA)
Содержание DigitalDNA ColdFire MCF5272
Страница 1: ...MCF5272UM D Rev 0 02 2001 MCF5272 ColdFire Integrated Microprocessor User s Manual ...
Страница 38: ...xxxviii MCF5272 User s Manual TABLES Table Number Title Page Number ...
Страница 58: ...1 10 MCF5272 User s Manual MCF5272 Specific Features ...
Страница 90: ...2 42 MCF5272 User s Manual Exception Processing Overview ...
Страница 96: ...3 6 MCF5272 User s Manual MAC Instruction Execution Timings ...
Страница 158: ...5 46 MCF5272 User s Manual Motorola Recommended BDM Pinout ...
Страница 184: ...7 12 MCF5272 User s Manual Interrupt Controller Registers ...
Страница 338: ...13 44 MCF5272 User s Manual Application Examples ...
Страница 414: ...18 6 MCF5272 User s Manual PWM Programming Model ...
Страница 452: ...19 38 MCF5272 User s Manual Power Supply Pins ...
Страница 482: ...20 30 MCF5272 User s Manual Reset Operation ...
Страница 492: ...21 10 MCF5272 User s Manual Non IEEE 1149 1 Operation ...
Страница 548: ...INDEX Index 12 MCF5272 User s Manual ...