TLK2501

1.5 TO 2.5 GBPS TRANSCEIVER

SLLS427D − AUGUST 2000 − REVISED JULY 2003

12

POST OFFICE BOX 655303

synchronization and initialization (continued)

If during normal transmission and reception, an invalid code is received, the TLK2501 notifies the attached

system or protocol device as described in comma detect and 8-bit/10-bit decoding. The synchronization state

machine transitions to the CHECK state. The CHECK state determines whether the invalid code received was

caused by a spurious event or a loss of the link. If, in the CHECK state, the decoder sees 4 consecutive valid

codes, the state machine determines the link is good and transitions back to the SYNC state for normal

operation. If, in the CHECK state, the decoder sees 3 invalid codes (not required to be consecutive), the

TLK2501 determines a loss of the link has occurred and transition the synchronization-state machine back to

the link-acquisition state (ACQ).

The state of the transmit data bus, control terminals, and serial outputs during the link acquisition process is

illustrated in Figure 7.

ACQ

D0−D15

DOUTTXP,

DOUTTXN

TXD(0−15)

TX_ER

Ca. Ext.

Error

IDLE

SYNC

TX_EN

D0−D15

xx

xx

xx

xx

xx

xx

xx

xx

xx

xx

xx

xx

xx

xx

xx

xx

xx

xx

xx

xx

xx

xx

Figure 7. Transmit Side Timing Diagram

The state of the receive data bus, status terminals, and serial inputs during the link acquisition process is

illustrated in Figure 8 and Figure 9.

ACQ

RX_DV,

RXD(0−15)

SYNC

DINRXP,

D0−D15

IDLE or Carrier

Extend

IDLE or Carrier

Extend

IDLE or Carrier

Extend

DINRXN

D0−D15

IDLE or Carrier

Extend

IDLE or Carrier

Extend

XXXXXXXXXXXXXXXXXXX

RESET

(Internal Signal)

RX_ER

Figure 8. Receive Side Timing Diagram (Idle or Carrier Extend)