ICS1893BY-10 - Release
Chapter 9 DC and AC Operating Conditions
9.5.19 10Base-T: Heartbeat Timing (SQE)
Table 9-26 lists the significant time periods for the 10Base-T heartbeat (that is, the Signal Quality Error).
The time periods consist of timings of signals on the following pins:
• TXEN
• TXCLK
• COL
Figure 9-20 shows the timing diagram for the time periods.
Note:
1. For more information on 10Base-T SQE operations, see Section 6.5.10, “10Base-T Operation: SQE
Test”.
2. In 10Base-T mode, one bit time = 100 ns.
Table 9-26. 10Base-T Heartbeat (SQE) Timing
Time
Parameter
Conditions
Min. Typ. Max. Units
Period
t1
t2
COL Heartbeat Assertion Delay from 10Base-T Half Duplex
TXEN De-Assertion
–
–
850
1500
ns
ns
COL Heartbeat Assertion Duration
10Base-T Half Duplex
1000 1500
Figure 9-20. 10Base-T Heartbeat (SQE) Timing Diagram
TXEN
TXCLK
COL
t1
t2
ICS1893BY-10 Rev A 3/24/04
March, 2004
Copyright © 2004, Integrated Circuit Systems, Inc.
All rights reserved.
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