AT89C5132
Figure 23-9. External 8-bit Bus Cycle – Data Write Waveforms
ALE
TLHLL
TWHLH
TLLWL
TWLWH
WR
TAVWL
TLLAX
TAVLL
TQVWH
TWHQX
P0
P2
A7:0
D7:0
Data Out
A15:8
23.3.2
External IDE 16-bit Bus Cycles
23.3.2.1
Definition of Symbols
Table 111. External IDE 16-bit Bus Cycles Timing Symbol Definitions
Signals
Conditions
High
A
D
L
Address
Data In
ALE
H
L
Low
V
X
Z
Valid
Q
R
W
Data Out
RD
No Longer Valid
Floating
WR
23.3.2.2
Timings
Test conditions: capacitive load on all pins = 50 pF.
161
4173E–USB–09/07