PSD813F2, PSD833F2, PSD834F2, PSD853F2, PSD854F2
44/110
PSD Interface to a Multiplexed 8-Bit Bus
Figure
19
shows an example of a system using a
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
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.
Figure 19. An Example of a Typical 8-bit Multiplexed Bus Interface
MCU
WR
RD
BHE
ALE
RESET
AD[7:0]
A[15:8]
A[15:8]
(OPTIONAL)
A[7:0]
ADIO
PORT
PORT
A
PORT
B
PORT
C
WR (CNTRL0)
RD (CNTRL1)
BHE (CNTRL2)
RST
ALE (PD0)
PORT D
(OPTIONAL)
PSD
AI02878C