DP83934CVUL20 National Semiconductor, DP83934CVUL20 Datasheet - Page 49

• Manufacturer Part Number: DP83934CVUL20
• Manufacturer: National Semiconductor

Specifications of DP83934CVUL20

• Operating Supply Voltage (typ): 5V
• Operating Supply Voltage (min): 4.75V
• Operating Supply Voltage (max): 5.25V
• Operating Temperature Classification: Commercial
• Mounting: Surface Mount
• Pin Count: 160
• Lead Free Status / RoHS Status: Not Compliant

6 0 SONIC-T Registers
6 3 6 Interrupt Status Register (Continued)
Bit
8
7
6
5
4
3
2
1
0
TXER TRANSMIT ERROR
Indicates that a packet has been transmitted with at least one of the following errors
The TXpkt status field reveals the cause of the error(s)
TC GENERAL PURPOSE TIMER COMPLETE
Indicates that the timer has rolled over from 0000 0000h to FFFF FFFFh (See Section 6 3 12 )
RDE RECEIVE DESCRIPTORS EXHAUSTED
Indicates that all receive packet descriptors in the RDA have been exhausted This bit is set when the SONIC-T
detects EOL
RBE RECEIVE BUFFER EXHAUSTED
Indicates that the SONIC-T has detected the Resource Read Pointer (RRP) is equal to the Resource Write Pointer
(RWP) This bit is set after the last field is read from the resource area (See Section 5 4 7 )
Note 1 This bit will be set as the SONIC-T finishes using the second to last receive buffer and reads the last RRA descriptor This gives the system
an early warning of impending no resources
Note 2 The SONIC-T will stop reception of packets when the last RBA has been used and will not continue reception until additional receive buffers
have been added (i e RWP is incremented beyond RRP) and this bit has been reset
Note 3 If additional buffers have been added resetting this bit causes the SONIC-T to read the next resource descriptor pointed to by the RRP in
the Receive Resource Area Note that resetting this bit under this condition is similar to issuing the Read RRA command (setting the RRRA bit in the
Command Register) This bit should never be reset until after the additional resources have been added to the RRA
RBAE RECEIVE BUFFER AREA EXCEEDED
Indicates that during reception the SONIC-T has reached the end of the Receive Buffer Area Reception is aborted
and the SONIC-T fetches the next available resource descriptors in the RRA The buffer space is not re-used and an
RDA is not set up for the truncated packet (see Section 5 4 7)
CRC CRC TALLY COUNTER ROLLOVER
Indicates that the tally counter has rolled over from FFFFh to 0000h (See Section 6 3 11 )
FAE FRAME ALIGNMENT ERROR (FAE) TALLY COUNTER ROLLOVER
Indicates that the FAE tally counter has rolled over from FFFFh to 0000h (See Section 6 3 11 )
MP MISSED PACKET (MP) COUNTER ROLLOVER
Indicates that the MP tally counter has rolled over from FFFFh to 0000h (See Section 6 3 11 )
RFO RECEIVE FIFO OVERRUN
Indicates that the SONIC-T has been unable to access the bus before the receive FIFO has filled from the network
This condition is due to excessively long bus latency and or slow bus clock Note that FIFO underruns are indicated
in the TCR (See Section 3 5 1 )
Byte count mismatch (BCM)
Excessive collisions (EXC)
FIFO underrun (FU)
Excessive deferral (EXD)
e
1 (See Section 5 4 7 )
(Continued)
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Description