DP83840AVCE National Semiconductor, DP83840AVCE Datasheet - Page 56

• Manufacturer Part Number: DP83840AVCE
• Description: IC ETHERNET PHYS LAYER 100-PQFP
• Manufacturer: National Semiconductor

Specifications of DP83840AVCE

• Controller Type: Ethernet Controller, 10Base-T
• Interface: IEEE 802.3af
• Voltage - Supply: 4.75 V ~ 5.25 V
• Current - Supply: 335mA
• Operating Temperature: 0°C ~ 70°C
• Mounting Type: Surface Mount
• Package / Case: 100-MQFP, 100-PQFP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Other names: *DP83840AVCE

Version A
4.0 Registers
4.16 10BASE-T STATUS REGISTER (10BTSR)
Address 1Bh
4.17 10BASE-T CONFIGURATION REGISTER (10BTCR)
Address 1Ch
15:10
14:8
8:0
Bit
Bit
15
9
7
6
5
4
3
2
1
10BT_SER
Bit Name
Bit Name
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
UTP/STP
Reserved
LP_EN
HBE
LSS
(Continued)
(Pin #98), RW
Default
Default
1, RW
1, RW
1, RW
1, RW
1, RW
0, RW
X, RO
X, RO
0, RO
0, RO
0, RO
RESERVED: Write as 0, read as don't care.
10BASE-T SERIAL MODE: The value on the 10BTSER pin (98) is
latched into this bit at power-up/reset.
1 = 10BASE-T serial mode selected (see Sections 2.5 and 3.1.3.3 for
more details)
0 = 10BASE-T nibble mode selected (see Section 3.1.3.2)
Serial mode is not supported for 100 Mb/s operation.
RESERVED: Write as 0, read as don't care.
RESERVED: Write as 1, read as don't care.
RESERVED: Write as 0, read as don't care.
RESERVED: Write as 1, read as don't care.
RESERVED: Write as 0, read as don't care.
LINK PULSE ENABLE:
1 = Transmission of link pulses enabled
0 = Link pulses disabled, good link condition forced
When configured for 100 Mb/s operation with Auto-Negotiation enabled,
clearing this bit will force the DP83840A into 10 Mb/s operation with link
pulses disabled.
If the DP83840A has been configured for 100 Mb/s operation with Auto-
Negotiation disabled, this bit will not affect operation.
HEARTBEAT ENABLE:
1 = Heartbeat function enabled
0 = Heartbeat function disabled
When the DP83840A is configured for Full Duplex operation, this bit will
be ignored (the collision/heartbeat function has no meaning in Full
Duplex mode). This bit has no meaning in 100 Mb/s mode.
UTP/STP MEDIA SELECT: Selects between the Unshielded Twisted
Pair (UTP) transmit outputs (TXU+/-) and the Shielded Twisted Pair
(STP) transmit outputs (TXS+/-).
1 = UTP selected
0 = STP selected
The pair that is not selected will tri-state.
LOW SQUELCH SELECT: Selects between standard 10BASE-T
receiver squelch threshold and a reduced squelch threshold that is
useful for longer cable applications and/or STP operation.
1 = Low Squelch Threshold selected
0 = Normal 10BASE-T Squelch Threshold selected
RESERVED: Write as 0, read as don't care.
Only one output pair (TXU+/- or TXS+/-) may be selected at one time.
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Description
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