PSD813F1 STMICROELECTRONICS [STMicroelectronics], PSD813F1 Datasheet - Page 39

• Manufacturer Part Number: PSD813F1
• Description: Flash In-System Programmable ISP Peripherals For 8-bit MCUs
• Manufacturer: STMICROELECTRONICS [STMicroelectronics]

Preliminary
The
PSD813F1
Functional
Blocks
(cont.)
Each of the two PLDs has unique characteristics suited for its applications They are
described in the following sections.
9.2.1 Decode PLD (DPLD)
The DPLD, shown in Figure 12, is used for decoding the address for internal and external
components. The DPLD can generate the following decode signals:
9.2.2 Complex PLD (CPLD)
The CPLD can be used to implement system logic functions, such as loadable counters
and shift registers, system mailboxes, handshaking protocols, state machines, and random
logic. The CPLD can also be used to generate 3 external chip selects, routed to Port D.
Although external chip selects can be produced by any Output Micro Cell, these three
external chip selects on Port D do not consume any Output Micro Cells.
As shown in Figure 11, the CPLD has the following blocks:
Each of the blocks are described in the subsections that follow.
The Input and Output Micro Cells are connected to the PSD813F1 internal data bus and
can be directly accessed by the microcontroller. This enables the MCU software to load
data into the Output Micro Cells or read data from both the Input and Output Micro Cells.
This feature allows efficient implementation of system logic and eliminates the need to
connect the data bus to the AND logic array as required in most standard PLD macrocell
architectures.
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8 sector selects for the main Flash memory (three product terms each)
4 sector selects for the EEPROM memory
(three product terms each)
1 internal SRAM select signal (two product terms)
1 internal CSIOP (PSD configuration register) select signal
1 JTAG select signal (enables JTAG on Port C)
2 internal peripheral select signals (peripheral I/O mode).
24 Input Micro Cells (IMCs)
16 Output Micro Cells (OMCs)
Micro Cell Allocator
Product Term Allocator
AND array capable of generating up to 137 product terms
Four I/O ports.
PSD813F1-A
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