CS8952T-CQ Cirrus Logic, CS8952T-CQ Datasheet - Page 19

• Manufacturer Part Number: CS8952T-CQ
• Description: 100BASE E-X AND 10BASE-T TRANSCEIVER
• Manufacturer: Cirrus Logic

Carrier Sense Operation
The CRS pin (Carrier Sense) is asserted when ei-
ther the transmitter is active or the receiver detects
at least two non-contiguous ZEROS within any 10
bits in the received data stream. Once asserted, it
will remain asserted until the transmitter has gone
idle or the receiver detects 10 consecutive ONES.
CRS is not synchronous to RX_CLK. It may tran-
sition at any time.
Link Integrity Monitor
The link integrity monitor determines whether the
underlying receive channel is providing reliable
data.
When auto-negotiation is disabled, the link is con-
sidered to be stable when the receiver has detected
DS206TPP2
CS8952T
CrystalLAN™ 100BASE-X and 10BASE-T Transceiver
CONTROL (Note 1)
CODE VIOLATIONS
Name
V0
V1
V2
V3
V4
V5
V6
V7
V8
V9
R
H
K
T
J
I
1. CONTROL code groups become violations when found in the data portion of the frame.
2. Invalid code groups are mapped to 5h unless the Code Error Report select bit in the Loopback,
Bypass, and Receiver Error Mask Register (address 18h) is set, in which case invalid code groups are
mapped to 6h.
5-bit Symbol
10001
00100
00000
00001
00010
00101
01000
10000
11000
01101
00111
00011
00110
01100
11001
11111
CIRRUS LOGIC ADVANCED PRODUCT DATABOOK
0110 or 0101 (Note 2)
0110 or 0101 (Note 2)
0110 or 0101 (Note 2)
0110 or 0101 (Note 2)
0110 or 0101 (Note 2)
0110 or 0101 (Note 2)
0110 or 0101 (Note 2)
0110 or 0101 (Note 2)
0110 or 0101 (Note 2)
0110 or 0101 (Note 2)
Code Violations (RX_ER = 1 or TX_ER = 1)
Normal Mode 4-bit
Table 3. 4B5B Code Violation Decoding
Nibble
0000
0000
0000
0000
0000
0000
Error Report
valid signal levels for at least 1 ms. If the signal
levels fall below the minimum for more than
350 us, the Link Status bit in the Basic Mode Status
Register (address 01h) is cleared, the Link Status
Change bit in the Interrupt Status Register (address
11h) is set, and the Disconnect Count Register (ad-
dress 12h) is incremented.
When auto-negotiation is enabled, the link will be
further qualified by the detection 100BASE-X
mode and 12 consecutive IDLE code groups.
Collision Detection
For half duplex, a collision is detected when the re-
ceiver and transmitter are active simultaneously.
Collisions are reported by asserting the COL pin.
Mode 4-bit
Nibble
0000
0000
0000
0000
0000
0000
0001
1000
1001
1010
1011
1100
1101
0111
1110
1111
This portion of the table relates received
5-bit symbols to received 4-bit nibbles
only. The control code groups may not
be transmitted in the data portion of the
frame.
Comments
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