PSD303B-70M STMicroelectronics, PSD303B-70M Datasheet - Page 22

• Manufacturer Part Number: PSD303B-70M
• Description: MCU 8BIT PROGRM 70NS 44-PQFP
• Manufacturer: STMicroelectronics

Specifications of PSD303B-70M

• Applications: *
• Interface: *
• Voltage - Supply: *
• Package / Case: 44-MQFP, 44-PQFP
• Mounting Type: Surface Mount
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

10.
I/O Port
Functions
(
cont.)
Figure 6. Port B Pin Structure
10.3.2 Port B (PB0-PB7) in 16-bit Multiplexed Address/Data Mode
In this mode, Port B becomes the low-order data bus byte to the MCU chip. When reading
an internal high-order location, data is presented on Port B pins to the MCU. When writing
to an internal high-order location, data present on Port B pins from the MCU is written to the
desired location.
NOTE: 1. CMOS/OD determines whether the output is open drain or CMOS.
N
R
N
C
O
U
T
E
A
L
S
T
U
C
S
I
B
S
0
7
•
•
•
RESET
D
A
A
D
D
N
T
E
R
N
A
T
U
8
1
5
L
B
S
•
•
•
I
WRITE DATA
WRITE DIR
READ DATA
READ DIR
CK
CK
D
D
R
R
DFF
DIR
FF
CSn
Dn
MCU
OUT
I/O
MUX
READ PIN
CONTROL
CMOS/OD
(1)
ENABLE
PSD3XX Family
PSD3XX Family
PORT B PIN
19