AM186 Datasheet, PDF (67/112 Pages) Advanced Micro Devices – High-Performance, 80C186- and 80C188-Compatible, 16-Bit Embedded Microcontrollers with RAM

COMMERCIAL AND INDUSTRIAL SWITCHING CHARACTERISTICS AND WAVEFORMS
In the switching waveforms that follow, several
abbreviations are used to indicate the specific periods
of a bus cycle. These periods are referred to as time
states. A typical bus cycle is composed of four
consecutive time states: t₁, t₂, t₃, and t₄. Wait states,
which represent multiple t₃ states, are referred to as t_w
states. When no bus cycle is pending, an idle (t_i) state
occurs.
In the switching parameter descriptions, the
multiplexed address is referred to as the AD address
bus; the nonmultiplexed address is referred to as the A
address bus.
Key to Switching Waveforms
WAVEFORM
INPUT
OUTPUT
Must be
Steady
Will be
Steady
D
May
Change
from H to L
Will be
Changing
from H to L
May
Change
from L to H
Don’t Care,
Any Change
Permitted
F _{Does Not}
Apply
R ^AInvalid
Will be
Changing
from L to H
Changing,
State
Unknown
Center
Line is High-
Impedance
Off State
Invalid
T
Am186^TMER and Am188^TMER Microcontrollers Data Sheet
67