P89V51RD2FN NXP Semiconductors, P89V51RD2FN Datasheet - Page 66

• Manufacturer Part Number: P89V51RD2FN
• Description: MCU 8-Bit 89V 80C51 CISC 64KB Flash 5V 40-Pin PDIP Tube
• Manufacturer: NXP Semiconductors

Specifications of P89V51RD2FN

• Package: 40PDIP
• Device Core: 80C51
• Family Name: 89V
• Maximum Speed: 40 MHz
• Ram Size: 1 KB
• Program Memory Size: 64 KB
• Operating Supply Voltage: 5 V
• Data Bus Width: 8 Bit
• Program Memory Type: Flash
• Number Of Programmable I/os: 32
• Interface Type: SPI/UART
• Operating Temperature: -40 to 85 °C
• Number Of Timers: 3

NXP Semiconductors
P89V51RB2_RC2_RD2_5
Product data sheet
Fig 31. External program memory read cycle
PSEN
port 0
port 2
ALE
9.1 Explanation of symbols
Each timing symbol has 5 characters. The first character is always a ‘T’ (stands for time).
The other characters, depending on their positions, stand for the name of a signal or the
logical status of that signal. The following is a list of all the characters and what they stand
for.
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 — High impedance (Float)
Example:
t
t
AVLL
LLPL
t
= Address valid to ALE LOW time
= ALE LOW to PSEN LOW time
AVLL
t
LHLL
t
LLAX
A0 to A7
Rev. 05 — 12 November 2009
t
LLPL
t AVIV
A8 to A15
t
PLAZ
t
t
PLIV
LLIV
INSTR IN
t
PXIX
t
PXIZ
P89V51RB2/RC2/RD2
t
PLPH
8-bit microcontrollers with 80C51 core
t
PXAV
A0 to A7
A8 to A15
002aaa548
© NXP B.V. 2009. All rights reserved.
66 of 80