DP83815CVNG National Semiconductor, DP83815CVNG Datasheet - Page 41

• Manufacturer Part Number: DP83815CVNG
• Description: IC CONTROLLER MEDIA ACCESS
• Manufacturer: National Semiconductor

Specifications of DP83815CVNG

• Controller Type: Ethernet Controller, MAC/BIU
• Interface: PCI
• Voltage - Supply: 3.3V
• Current - Supply: 170mA
• Operating Temperature: 0°C ~ 70°C
• Mounting Type: Surface Mount
• Package / Case: 144-LQFP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Other names: *DP83815CVNG

4.0 Register Set
4.2.1 Command Register
This register is used for issuing commands to DP83815. These commands are issued by setting the corresponding bits
for the function. A global software reset along with individual reset and enable/disable for transmitter and receiver are
provided here.
31-9
Bit
8
7
6
5
4
3
2
1
0
Bit Name
RXR
RXD
RXE
RST
SWI
TXR
TXD
TXE
Offset: 0000h
(Continued)
Tag: CR
unused
Reset
Set to 1 to force the DP83815 to a soft reset state which disables the transmitter and receiver,
reinitializes the FIFOs, and resets all affected registers to their soft reset state. This operation implies
both a TXR and a RXR. This bit will read back a 1 during the reset operation, and be cleared to 0 by the
hardware when the reset operation is complete. EEPROM configuration information is not loaded here.
Software Interrupt
Setting this bit to a 1 forces the DP83815 to generate a hardware interrupt. This interrupt is mask-able
via the IMR.
unused
Receiver Reset
When set to a 1, this bit causes the current packet reception to be aborted, the receive data and status
FIFOs to be flushed, and the receive state machine to enter the idle state (RXE goes to 0). This is a
write-only bit and is always read back as 0.
Transmit Reset
When set to a 1, this bit causes the current transmission to be aborted, the transmit data and status
FIFOs to be flushed, and the transmit state machine to enter the idle state (TXE goes to 0). This is a
write-only bit and is always read back as 0.
Receiver Disable
Disable the receive state machine after any current packets in progress. When this operation has been
completed the RXE bit will be cleared to 0. This is a write-only bit and is always read back as 0. The
driver should not set both RXD and RXE in the same write, the RXE will be ignored, and RXD will have
precedence.
Receiver Enable
When set to a 1, and the receive state machine is idle, then the receive machine becomes active. This bit
will read back as a 1 whenever the receive state machine is active. After initial power-up, software must
insure that the receiver has completely reset before setting this bit (See ISR:RXRCMP).
Transmit Disable
When set to a 1, halts the transmitter after the completion of the current packet. This is a write-only bit
and is always read back as 0. The driver should not set both TXD and TXE in the same write, the TXE
will be ignored, and TXD will have precedence.
Transmit Enable
When set to a 1, and the transmit state machine is idle, then the transmit state machine becomes active.
This bit will read back as a 1 whenever the transmit state machine is active. After initial power-up,
software must insure that the transmitter has completely reset before setting this bit (See ISR:TXRCMP).
Access: Read Write
Size: 32 bits
41
Description
Hard Reset: 00000000h
Soft Reset: 00000000h
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