80C528 Datasheet, PDF (16/26 Pages) NXP Semiconductors – CMOS single-chip 8-bit microcontroller

Philips Semiconductors
CMOS single-chip 8-bit microcontrollers
Product specification
80C528/83C528
EXPLANATION OF THE AC SYMBOLS
Each timing symbol has five characters. The Q – Output data
first character is always ‘t’ (= time). The other R – RD signal
characters, depending on their positions,
t – Time
indicate the name of a signal or the logical
V – Valid
status of that signal. The designations are:
W – WR signal
A – Address
X – No longer a valid logic level
C – Clock
Z – Float
D – Input data
H – Logic level high
Examples: t_AVLL = Time for address valid
to ALE low.
I – Instruction (program memory contents)
L – Logic level low, or ALE
t_LLPL = Time for ALE low to
PSEN low.
P – PSEN
ALE
PSEN
PORT 0
PORT 2
t_LHLL
t_AVLL
t_LLAX
A0–A7
t_PLPH
t_LLPL
t_LLIV
t_PLIV
t_PLAZ
t_PXIX
t_PXIZ
INSTR IN
t_AVIV
A8–A15
A0–A7
A8–A15
Figure 1. External Program Memory Read Cycle
ALE
PSEN
RD
PORT 0
PORT 2
t_LLDV
t_LLWL
t_RLRH
t_WHLH
t_AVLL
t_LLAX
A0–A7
FROM RI OR DPL
t_RLAZ
t_RLDV
t_RHDX
DATA IN
t_AVWL
t_AVDV
P2.0–P2.7 OR A8–A15 FROM DPH
t_RHDZ
A0–A7 FROM PCL
A8–A15 FROM PCH
Figure 2. External Data Memory Read Cycle
1995 Feb 02
16
INSTR IN