AT89S51_08 Datasheet, PDF (2/31 Pages) ATMEL Corporation – 8-bit Microcontroller with 4K Bytes In-System Programmable Flash

2. Pin Configurations
2.1
40-lead PDIP
P1.0 1
P1.1 2
P1.2 3
P1.3 4
P1.4 5
(MOSI) P1.5 6
(MISO) P1.6 7
(SCK) P1.7 8
RST 9
(RXD) P3.0 10
(TXD) P3.1 11
(INT0) P3.2 12
(INT1) P3.3 13
(T0) P3.4 14
(T1) P3.5 15
(WR) P3.6 16
(RD) P3.7 17
XTAL2 18
XTAL1 19
GND 20
40 VCC
39 P0.0 (AD0)
38 P0.1 (AD1)
37 P0.2 (AD2)
36 P0.3 (AD3)
35 P0.4 (AD4)
34 P0.5 (AD5)
33 P0.6 (AD6)
32 P0.7 (AD7)
31 EA/VPP
30 ALE/PROG
29 PSEN
28 P2.7 (A15)
27 P2.6 (A14)
26 P2.5 (A13)
25 P2.4 (A12)
24 P2.3 (A11)
23 P2.2 (A10)
22 P2.1 (A9)
21 P2.0 (A8)
2.2 44-lead TQFP
(MOSI) P1.5 1
(MISO) P1.6 2
(SCK) P1.7 3
RST 4
(RXD) P3.0 5
NC 6
(TXD) P3.1 7
(INT0) P3.2 8
(INT1) P3.3 9
(T0) P3.4 10
(T1) P3.5 11
33 P0.4 (AD4)
32 P0.5 (AD5)
31 P0.6 (AD6)
30 P0.7 (AD7)
29 EA/VPP
28 NC
27 ALE/PROG
26 PSEN
25 P2.7 (A15)
24 P2.6 (A14)
23 P2.5 (A13)
2.3 44-lead PLCC
(MOSI) P1.5 7
(MISO) P1.6 8
(SCK) P1.7 9
RST 10
(RXD) P3.0 11
NC 12
(TXD) P3.1 13
(INT0) P3.2 14
(INT1) P3.3 15
(T0) P3.4 16
(T1) P3.5 17
39 P0.4 (AD4)
38 P0.5 (AD5)
37 P0.6 (AD6)
36 P0.7 (AD7)
35 EA/VPP
34 NC
33 ALE/PROG
32 PSEN
31 P2.7 (A15)
30 P2.6 (A14)
29 P2.5 (A13)
2 AT89S51
2487D–MICRO–6/08