DP83865-EB National Semiconductor, DP83865-EB Datasheet - Page 22
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DP83865-EB
Manufacturer Part Number
DP83865-EB
Description
BOARD EVALUATION DP83865
Manufacturer
National Semiconductor
Datasheet
1.DP83865BVH.pdf
(86 pages)
Specifications of DP83865-EB
Main Purpose
Interface, Ethernet
Utilized Ic / Part
DP83865
Lead Free Status / RoHS Status
Not applicable / Not applicable
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2.0 Register Block
5:0
Bit
11
10
15
14
13
9
8
7
6
Collision Test
Power_Down
100BASE-T4
100BASE-X
100BASE-X
Restart_AN
Half Duplex
Full Duplex
Bit Name
Reserved
Speed[1]
Duplex
Isolate
(Continued)
Table 3. Basic Mode Control Register (BMCR) address 0x00
Table 4. Basic Mode Status Register (BMSR) address 0x01
STRAP[1], RW Duplex Mode:
STRAP[0], RW Speed Select: See description for bit 13.
0, RW, SC
Default
0, RW
0, RW
0, RW
0, RO
0, P
1, P
1, P
Power Down:
1 = Power down (only Management Interface and logic active.)
0 = Normal operation.
Note: This mode is internally the same as isolate mode (bit 10).
Isolate:
1 = Isolates the Port from the MII/GMII with the exception of the
serial management. When this bit is asserted, the DP83865 does
not respond to TXD[7:0], TX_EN, and TX_ER inputs, and it pre-
sents a high impedance on TX_CLK, RX_CLK, RX_DV, RX_ER,
RXD[7:0], COL and CRS outputs.
0 = Normal operation.
Restart Auto-Negotiation:
1 = Restart Auto-Negotiation. Re-initiates the Auto-Negotiation
process. If Auto-Negotiation is disabled (bit 12 = 0), this bit is ig-
nored. This bit is self-clearing and will return a value of 1 until
Auto-Negotiation is initiated, whereupon it will self-clear. Opera-
tion of the Auto-Negotiation process is not affected by the man-
agement entity clearing this bit.
0 = Normal operation.
1 = Full Duplex operation. Duplex selection is allowed only when
Auto-Negotiation is disabled (AN_EN = 0).
0 = Half Duplex operation.
(The default value of this bit is = to the strap value of pin 9 during
reset/power-on IF Auto-Negotiation is disabled.)
Collision Test:
1 = Collision test enabled.
0 = Normal operation.
When set, this bit will cause the COL signal to be asserted in re-
sponse to the assertion of TX_EN withinTBD-bit times. The COL
signal will be de-asserted within 4-bit times in response to the de-
assertion of TX_EN.
(The default value of this bit is = to the strap value of pin 8 during
reset/power-on IF Auto-Negotiation is disabled.)
Reserved by IEEE: Write ignored, read as 0.
100BASE-T4 Capable:
0 = Device not able to perform 100BASE-T4 mode.
DP83865 does not support 100BASE-T4 mode and bit should al-
ways be read back as “0”.
100BASE-X Full Duplex Capable:
1 = Device able to perform 100BASE-X in Full Duplex mode.
100BASE-X Half Duplex Capable:
1 = Device able to perform 100BASE-X in Half Duplex mode.
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Description