~ National ~ Semiconductor - Al Kossow's Bitsavers

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15.0 Switching Characteristics (Continued)
BSCK
ADSO
T1
Walt State Insertion
T2
13 TW T4
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TL/F/9345-44
Symbol
ews
ewr
Parameter
External Wait Setup to T3..l. Clock
(Note 1)
External Wait Release Time
(Note 1)
Min Max Units
10 ns
15 ns
Nota 1: The addition of wait.tates affects the count of deserialized bytes and is limHed to a number of bus clock cycles depending on the bus clock and network
rates. The allowable waH states are found in the table below. (Assumas 1 Mbitisec data rate.)
BUSCK(MHz)
Byte Transfer
'" of Walt States
Word Transfer
The number of allowable wait states in byte mode can be calculated using:
*W(by1emodO) - C.:::k
-1)
1 0 1 #W - Number of Walt States
2 2 4
tnw - Network Clock Period
!bsck - BSCK Period
4 6 9 Tha number of allowable waH states in word mode can be calculated using:
8 13
Table assumes 1 MHz network clock.
19 ( 5tnw )
#W(word modo) - 2tbsck- 1
1·95