LM3S6950 Luminary Micro, Inc, LM3S6950 Datasheet - Page 403

• Manufacturer Part Number: LM3S6950
• Description: Lm3s6950 Arm Microcontroller
• Manufacturer: Luminary Micro, Inc

Reset
Reset
Type
Type
Ethernet MAC Management Divider (MACMDV)
Base 0x4004.8000
Offset 0x024
Type R/W, reset 0x0000.0080
July 25, 2008
Bit/Field
31:8
7:0
RO
RO
31
15
0
0
Register 11: Ethernet MAC Management Divider (MACMDV), offset 0x024
This register enables software to set the clock divider for the Management Data Clock (MDC). This
clock is used to synchronize read and write transactions between the system and the MII Management
registers. The frequency of the MDC clock can be calculated from the following formula:
F
The clock divider must be written with a value that ensures that the MDC clock does not exceed a
frequency of 2.5 MHz.
RO
RO
30
14
0
0
mdc
= F
reserved
RO
RO
29
13
0
0
Name
DIV
ipclk
RO
RO
28
12
0
0
reserved
/ (2 * (MACMDVR + 1 ))
RO
RO
27
11
0
0
Type
R/W
RO
RO
RO
26
10
0
0
Reset
0x80
0x0
RO
RO
25
0
9
0
Preliminary
RO
RO
24
0
8
0
Description
Software should not rely on the value of a reserved bit. To provide
compatibility with future products, the value of a reserved bit should be
preserved across a read-modify-write operation.
Clock Divider
The DIV bits are used to set the clock divider for the MDC clock used
to transmit data between the MAC and PHY over the serial MII interface.
reserved
R/W
RO
23
0
7
1
R/W
RO
22
0
6
0
R/W
RO
21
0
5
0
R/W
RO
20
0
4
0
DIV
LM3S6950 Microcontroller
R/W
RO
19
0
3
0
R/W
RO
18
0
2
0
R/W
RO
17
0
1
0
R/W
RO
16
0
0
0
403