Enhanced Three-Speed Ethernet (eTSEC)
Figure 14 shows the TBI transmit AC timing diagram.
t
t
TTX
TTXR
GTX_CLK
TCG[9:0]
t
TTXH
t
TTXF
t
TTXF
t
t
TTXR
TTKHDV
t
TTKHDX
Figure 14. TBI Transmit AC Timing Diagram
8.2.4.2
TBI Receive AC Timing Specifications
Table 31 provides the TBI receive AC timing specifications.
Table 31. TBI Receive AC Timing Specifications
1
Parameter/Condition
TSECn_RX_CLK[0:1] clock period
Symbol
Min
Typ
Max
Unit
t
—
16.0
—
—
8.5
60
—
ns
ns
%
TRX
TSECn_RX_CLK[0:1] skew
t
7.5
40
SKTRX
TSECn_RX_CLK[0:1] duty cycle
t
/t
—
TRXH TRX
RCG[9:0] setup time to rising TSECn_RX_CLK
RCG[9:0] hold time to rising TSECn_RX_CLK
TSECn_RX_CLK[0:1] clock rise time (20%–80%)
TSECn_RX_CLK[0:1] clock fall time (80%–20%)
Notes:
t
t
2.5
1.5
0.7
0.7
—
ns
ns
ns
ns
TRDVKH
—
—
TRDXKH
2
t
—
2.4
2.4
TRXR
2
t
—
TRXF
1. The symbols used for timing specifications follow the pattern of t
for
(first two letters of functional block)(signal)(state)(reference)(state)
inputs and t
for outputs. For example, t
symbolizes TBI receive
(first two letters of functional block)(reference)(state)(signal)(state)
TRDVKH
timing (TR) with respect to the time data input signals (D) reach the valid state (V) relative to the t
clock reference (K)
TRX
going to the high (H) state or setup time. Also, t
symbolizes TBI receive timing (TR) with respect to the time data input
TRDXKH
signals (D) went invalid (X) relative to the t
clock reference (K) going to the high (H) state. Note that, in general, the clock
TRX
reference symbol representation is based on three letters representing the clock of a particular functional. For example, the
subscript of t represents the TBI (T) receive (RX) clock. For rise and fall times, the latter convention is used with the
TRX
appropriate letter: R (rise) or F (fall). For symbols representing skews, the subscript is skew (SK) followed by the clock that
is being skewed (TRX).
2. Guaranteed by design.
MPC8548E PowerQUICC™ III Integrated Processor Hardware Specifications, Rev. 6
34
Freescale Semiconductor
FREESCALE [ Freescale ]
