4-61
68PLCC
P1.0
(
T
2)
VCCP1.1
(
T
2
EX)
P0.0
(AD0)
P1.2
ALE/PROG
(RD)
P3.7
XT
AL1
EA/VPP
(WR)
P3.6 GND
(RXD) P3.0
P0.7 (AD7)
P2.6 (A14)
P0.6 (AD6)
P0.5 (AD5)
P0.4 (AD4)
P0.3
(AD3)
P0.2
(AD2)
P1.3 P0.1
(AD1)
PSEN
XT
AL2
(INT0) P3.2
(TXD) P3.1
(T1) P3.5
(INT1) P3.3
(T0) P3.4
P2.7 (A15)
(A11)
P2.3
(A12)
P2.4
(A10)
P2.2
(A
9)
P
2
.1
(A
8)
P
2
.0
NC
23
1
RST
INDEX
CORNER
NC
NC
P2.5 (A13)
34 NC
42
43
40
41
6
5
444
3
2
26
25
28
27
18
19
20 24
21
22
7
8
9
10
11
12
13
14
15
16
17 29
30
39
38
37
36
35
33
32
31
P1.4
P1.5
P1.6
P1.7
Features
• Compatible with MCS-51™ Products
• 8K Bytes of In-System Reprogrammable Flash Memory
– Endurance: 1,000 Write/Erase Cycles
• Fully Static Operation: 0 Hz to 24 MHz
• Three-Level Program Memory Lock
• 256 x 8-Bit Internal RAM
• 32 Programmable I/O Lines
• Three 16-Bit Timer/Counters
• Eight Interrupt Sources
• Programmable Serial Channel
• Low Power Idle and Power Down Modes
Description
The AT89C52 is a low-power, high-performance CMOS 8-bit microcomputer with 8K
bytes of Flash programmable and erasable read only memory (PEROM). The device
is manufactured using Atmel’s high density nonvolatile memory technology and is
compatible with the industry standard 80C51 and 80C52 instruction set and pinout.
The on-chip Flash allows the program memory to be reprogrammed in-system or by a
conventional nonvolatile memory programmer. By combining a versatile 8-bit CPU
with Flash on a monolithic chip, the Atmel AT89C52 is a powerful microcomputer
which provides a highly flexible and cost effective solution to many embedded control
applications.
0313F-A–12/97
8-Bit
Microcontroller
with 8K Bytes
Flash
AT89C52
PDIP
(T2) P1.0 VCC
(T2 EX) P1.1 P0.0 (AD0)
P1.2
(INT0) P3.2
ALE/PROG
(RD) P3.7 P2.3 (A11)
(TXD) P3.1
EA/VPP
(WR) P3.6 P2.4 (A12)
(RXD) P3.0
P0.7 (AD7)
(T1) P3.5
P2.6 (A14)
RST
P0.6 (AD6)
P0.5 (AD5)
P0.4 (AD4)
P0.3 (AD3)
P0.2 (AD2)P1.3
P0.1 (AD1)
(INT1) P3.3
PSEN
XTAL2 P2.2 (A10)
(T0) P3.4
P2.7 (A15)
XTAL1 P2.1 (A9)
GND P2.0 (A8)
P2.5 (A13)
20
19
18
17
16
15
1
2
3
4
5
6
7
8
9
10
11
12
13
14
21
22
23
24
25
26
40
39
38
37
36
35
34
33
32
31
30
29
28
27
P1.4
P1.5
P1.6
P1.7
Pin Configurations
PQFP/TQFP
23
1
INDEX
CORNER
34
P1.0
(
T
2)
VCCP1.1
(
T
2
EX)
P1.2P1.3 NC
42
43
40
41
6
5
4
44
3
2
26
25
28
27
24
18
19
20
21
22
NC
7
8
9
10
11
12
13
14
15
16
17
29
30
39
38
37
36
35
33
32
31
NC
PSEN
XT
AL1
GND
XT
AL2
GND
P0.0
(AD0)
ALE/PROG
(RD)
P3.7
EA/VPP
(WR)
P3.6
(RXD) P3.0
P0.7 (AD7)
P2.6 (A14)
P0.6 (AD6)
P0.5 (AD5)
P0.4 (AD4)
P0.3
(AD3)
P0.2
(AD2)
P0.1
(AD1)
(INT0) P3.2
(TXD) P3.1
(T1) P3.5
(INT1) P3.3
(T0) P3.4
P2.7 (A15)
(A11)
P2.3
(A12)
P2.4
(A10)
P2.2
(A
9)
P
2
.1
(A
8)
P
2
.0
RST
P2.5 (A13)
P1.4
P1.5
P1.6
P1.7
(continued)