p87c51mc2ba/02 NXP Semiconductors, p87c51mc2ba/02 Datasheet - Page 23

• Manufacturer Part Number: p87c51mc2ba/02
• Description: 80c51 8-bit Microcontroller Family With Extended Memory
• Manufacturer: NXP Semiconductors

Philips Semiconductors
9397 750 12302
Product data
11.1 Explanation of AC symbols
Each timing symbol has five characters. The first character is always ‘t’ (= time). The
other characters, depending on their positions, indicate the name of a signal or the
logical status of that signal. The designations are:
A — Address
C — Clock
D — Input data
H — Logic level HIGH
I — Instruction (program memory contents)
L — Logic level LOW, or ALE
P — PSEN
Q — Output data
R — RD signal
t — Time
V — Valid
W — WR signal
X — No longer a valid logic level
Z — Float
Examples:
t
t
AVLL
LLPL
— Time for address valid to ALE LOW
— Time for ALE LOW to PSEN LOW
Rev. 03 — 13 November 2003
P87C51MB2/P87C51MC2
80C51 8-bit microcontroller family
© Koninklijke Philips Electronics N.V. 2003. All rights reserved.
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