UPSD33XX Datasheet, PDF (205/231 Pages) STMicroelectronics – Fast 8032 MCU with Programmable Logic

uPSD33xx
Table 126. AC Signal Letters for Timing
A
Address
C
Clock
D
Input Data
I
Instruction
L
ALE
N
RESET Input or Output
P
PSEN signal
Q
Output Data
R
RD signal
W
WR signal
B
V_STBY Output
M
Output Macrocell
Note: Example: t_AVLX = Time from Address Valid to ALE Invalid.
Table 127. AC Signal Behavior Symbols for
Timing
t
Time
L
Logic Level Low or ALE
H
Logic Level High
V
Valid
X
No Longer a Valid Logic Level
Z
Float
PW
Pulse Width
Note: Example: tAVLX = Time from Address Valid to ALE Invalid.
Figure 87. Switching Waveforms – Key
WAVEFORMS
INPUTS
OUTPUTS
STEADY INPUT
STEADY OUTPUT
MAY CHANGE FROM
HI TO LO
MAY CHANGE FROM
LO TO HI
WILL BE CHANGING
FROM HI TO LO
WILL BE CHANGING
LO TO HI
DON'T CARE
OUTPUTS ONLY
CHANGING, STATE
UNKNOWN
CENTER LINE IS
TRI-STATE
AI03102
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