at89c51re2-slsem ATMEL Corporation, at89c51re2-slsem Datasheet - Page 151

• Manufacturer Part Number: at89c51re2-slsem
• Description: At89c51re2 8-bit Flash Microcontroller
• Manufacturer: ATMEL Corporation

AC Parameters
Explanation of the AC
Symbols
134
AT89C51RE2
Figure 49. I
Figure 50. I
Figure 51. Clock Signal Waveform for I
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.
Example:T
(Load Capacitance for port 0, ALE and PSEN = 100 pF; Load Capacitance for all other
outputs = 80 pF.)
Table 98 Table 101, and Table 104 give the description of each AC symbols.
Table 99, Table 100, Table 102 and Table 105 gives the range for each AC parameter.
T
LLPL
= Time for ALE Low to PSEN Low.
(NC)
AVLL
CLOCK
SIGNAL
CC
CC
= Time for Address Valid to ALE Low.
Test Condition, Idle Mode
Test Condition, Power-down Mode
(NC)
RST
XTAL2
XTAL1
V
SS
V
V
CC
RST
XTAL2
XTAL1
V
EA
CC
T
I
SS
P0
-0.5V
0.45V
CC
CHCL
V
T
CC
CLCH
V
EA
V
CC
P0
I
CC
CC
= T
V
CC
CHCL
V
CC
CC
= 5ns.
Tests in Active and Idle Modes
T
CLCH
0.7V
All other pins are disconnected.
0.2V
All other pins are disconnected.
CC
CC
-0.1
7663B–8051–03/07