PSD813F1A-12J STMICROELECTRONICS [STMicroelectronics], PSD813F1A-12J Datasheet - Page 48
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PSD813F1A-12J
Manufacturer Part Number
PSD813F1A-12J
Description
Flash In-System Programmable (ISP) Peripherals for 8-bit MCUs, 5V
Manufacturer
STMICROELECTRONICS [STMicroelectronics]
Datasheet
1.PSD813F1A-12J.pdf
(110 pages)
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Part Number:
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PSD813F1
80C251
The Intel 80C251 MCU features a user-config-
urable bus interface with four possible bus config-
urations, as shown in
The 80C251 has two major operating modes:
Page Mode and Non-Page Mode. In Non-Page
Mode, the data is multiplexed with the lower ad-
dress byte, and ALE is active in every bus cycle.
Table 17. Interfacing the PSD with the 80C251, with One READ Input
Note: 1. The A16 and A17 connections are optional.
48/110
RESET
RESET
2. In non-Page-Mode, AD7-AD0 connects to ADIO7-ADIO0.
20
13
14
15
16
17
10
35
21
11
4
2
3
5
6
7
8
9
80C251SB
P3.3/INT1
P3.4/T0
RST
EA
P1.0
P1.1
P1.2
P1.3
P1.4
P1.5
P1.6
P1.7
P3.0/RXD
P3.1/TXD
P3.2/INT0
P3.5/T1
X1
X2
Table 18., page
RD/A16
PSEN
P0.0
P0.1
P0.2
P0.3
P0.4
P0.5
P0.6
P0.7
P2.0
P2.1
P2.2
P2.3
P2.5
P2.6
P2.7
P2.4
ALE
WR
19
43
42
41
40
39
38
37
36
24
25
26
27
28
29
30
31
33
32
18
RESET
49.
A4
AD10
AD12
AD14
A0
A1
A2
A3
A5
A6
A7
AD8
AD9
AD11
AD13
AD15
ALE
RD
WR
A16
In Page Mode, data D[7:0] is multiplexed with ad-
dress A[15:8]. In a bus cycle where there is a Page
hit, the ALE signal is not active and only addresses
A[7:0] are changing. The PSD supports both
modes. In Page Mode, the PSD bus timing is iden-
tical to Non-Page Mode except the address hold
time and setup time with respect to ALE is not re-
quired. The PSD access time is measured from
address A[7:0] valid to data in valid.
A0
A1
A2
A3
A4
A5
A6
A7
AD8
AD9
AD10
AD12
AD13
AD11
AD14
AD15
30
31
32
33
34
35
36
37
39
40
41
42
43
44
46
50
49
10
48
45
47
9
8
PSD
ADIO0
ADIO1
ADIO2
ADIO3
ADIO4
ADIO5
ADIO6
ADIO7
ADIO8
ADIO9
ADIO10
ADIO11
ADIO12
ADIO13
ADIO14
ADIO15
CNTL0 ( WR )
CNTL1 ( RD )
CNTL 2(PSEN)
PD0-ALE
PD1
PD2
RESET
PC2
PC0
PC1
PC3
PC4
PC5
PC6
PC7
PA0
PA1
PA2
PA3
PA4
PA5
PA6
PA7
PB0
PB1
PB2
PB3
PB4
PB5
PB6
PB7
29
28
27
25
24
23
22
19
18
17
14
13
12
11
21
7
6
5
4
3
2
52
51
20
A16 1
AI02881C
A17 1