PSD813F1A-12J STMICROELECTRONICS [STMicroelectronics], PSD813F1A-12J Datasheet - Page 45

• Manufacturer Part Number: PSD813F1A-12J
• Description: Flash In-System Programmable (ISP) Peripherals for 8-bit MCUs, 5V
• Manufacturer: STMICROELECTRONICS [STMicroelectronics]

PSD Interface to a Multiplexed 8-Bit Bus
Figure
MCU with an 8-bit multiplexed bus and a PSD. The
ADIO port on the PSD is connected directly to the
MCU address/data bus. Address Strobe (ALE/AS,
PD0) latches the address signals internally.
Latched addresses can be brought out to Port A or
Figure 21. An Example of a Typical 8-bit Multiplexed Bus Interface
21
RESET
MCU
shows an example of a system using a
BHE
ALE
WR
RD
AD [ 7:0 ]
A [ 15:8 ]
B. The PSD drives the ADIO data bus only when
one of its internal resources is accessed and Read
Strobe (RD, CNTL1) is active. Should the system
address bus exceed sixteen bits, Ports A, B, C, or
D may be used as additional address inputs.
PSD
WR ( CNTRL0 )
RD ( CNTRL1 )
BHE ( CNTRL2 )
RST
ALE ( PD0 )
PORT D
PORT
ADIO
PORT
PORT
PORT
A
B
C
( OPTIONAL )
( OPTIONAL )
A [ 7: 0 ]
A [ 15: 8 ]
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