DP83907VF National Semiconductor, DP83907VF Datasheet - Page 30

• Manufacturer Part Number: DP83907VF
• Description: IC CONTROLLR AT/LANII TP 160PQFP
• Manufacturer: National Semiconductor

Specifications of DP83907VF

• Controller Type: Network Interface Controller (NIC)
• Interface: Twisted Pair
• Voltage - Supply: 4.75 V ~ 5.25 V
• Current - Supply: 150mA
• Operating Temperature: 0°C ~ 70°C
• Mounting Type: Surface Mount
• Package / Case: 160-MQFP, 160-PQFP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Other names: *DP83907VF

D3 –D5
D6 D7
5 0 Register Descriptions
COMMAND REGISTER (CR)
The Command Register is used to initiate transmissions enable or disable Remote DMA operations and to select register
pages To issue a command the microprocessor sets the corresponding bit(s) (RD2 RD1 RD0 TXP) Further commands may
be overlapped but with the following rules (1) If a transmit command overlaps with a remote DMA operation bits RD0 RD1
and RD2 must be maintained for the remote DMA command when setting the TXP bit Note if a remote DMA command is re-is-
sued when giving the transmit command the DMA will complete immediately if the remote byte count register has not been re-
initialized (2) If a remote DMA operation overlaps a transmission RD0 RD1 and RD2 may be written with the desired values
and a ‘‘0’’ written to the TXP bit Writing a ‘‘0’’ to this bit has no effect (3) A remote write DMA may not overlap remote read
operation or vice versa Either of these operations must either complete or be aborted before the other operation may start Bits
PS1 PS0 RD2 and STP may be set any time
Bit
D0
D1
D2
RD0 –RD2
PS0 PS1
Symbol
STP
STA
TXP
STOP Software reset command takes the controller off-line no packets will be received or transmitted
Any reception or transmission in progress will continue to completion before entering the reset state To
exit this state the STP bit must be reset and the STA bit must be set high To perform a software reset
this bit should be set high The software reset has executed only when indicated by the RST bit in the
ISR being set to 1 STP powers up high
Note If the DP83907 has previously been in start mode and the STP is set both the STP and STA bits will remain set
START This bit is used to activate the NIC Core after either power up or when the NIC Core has been
placed in a reset mode by software command or error STA powers up low
TRANSMIT PACKET This bit must be set to initiate transmission of a packet TXP is internally reset
either after the transmission is completed or aborted This bit should be set only after the Transmit Byte
Count and Transmit Page Start registers have been programmed
REMOTE DMA COMMAND These three encoded bits control operation of the Remote DMA channel
RD2 can be set to abort any Remote DMA command in progress The Remote Byte Count Registers
should be cleared when a Remote DMA has been aborted The Remote Start Addresses are not
restored to the starting address if the Remote DMA is aborted
RD2
Note 1 If a remote DMA operation is aborted and the remote byte count has not decremented to zero the data transfer port should
be read for a remote read or send packet or written to for a remote write This is required to ensure future correct operation
PAGE SELECT These two encoded bits select which register page is to be accessed with addresses
RA0 –3
PS1
0
0
0
0
1
0
0
1
1
PS1
7
RD1
PS0
X
00H (READ WRITE)
0
0
1
1
0
1
0
1
PS0
6
RD0
Register Page 0
Register Page 1
Register Page 2
Reserved
(Continued)
0
1
0
1
X
RD2
5
Not Allowed
Remote Read
Remote Write (Note 2)
Send Packet
Abort Complete Remote DMA (Note 1)
RD1
4
30
RD0
3
Description
TXP
2
STA
1
STP
0