PXS20RM Datasheet, PDF (48/1368 Pages) Freescale Semiconductor, Inc – PXS20 Microcontroller

Introduction
buffers. Prefetch buffer hits allow no-wait responses. Buffer misses incur a 3 wait state response at
120 MHz.
The flash memory module provides the following features
• 1 MB of flash memory in unique multi-partitioned hard macro
• Sectorization: 16 KB + 2 × 48 KB + 16 KB + 2 × 64 KB + 2 × 128 KB + 2 × 256 KB
• EEPROM emulation (in software) within same module but on different partition
• 16 KB test sector and 16 KB shadow sector for test, censorship device and user option bits
• Wait states:
— 3 wait states at 120 MHz
— 2 wait states at 80 MHz
— 1 wait state at 60 MHz
• Flash memory line 128-bit wide with 8-bit ECC on 64-bit word (total 144 bits)
• Accessed via a 64-bit wide bus for write and a 128-bit wide array for read operations
• 1-bit error correction, 2-bit error detection
1.4.6 On-Chip SRAM with ECC
The PXS20 SRAM provides a general-purpose single port memory.
ECC handling is done on a 32-bit boundary for data and it is extended to the address to have the highest
possible diagnostic coverage including the array internal address decoder.
The SRAM module provides the following features:
• System SRAM: 128 KB
• ECC on 32-bit word (syndrome of 7 bits)
— ECC covers SRAM bus address
• 1-bit error correction, 2-bit error detection
• Wait states:
— 1 wait state at 120 MHz
— 0 wait states at 80 MHz and 60 MHz
1.4.7 Platform Flash Memory Controller
The following list summarizes the key features of the flash memory controller:
• Single AHB port interface supports a 64-bit data bus. All AHB aligned and unaligned reads within
the 32-bit container are supported. Only aligned word writes are supported.
• Array interfaces support a 128-bit read data bus and a 64-bit write data bus for each bank.
• Code flash (bank0) interface provides configurable read buffering and page prefetch support.
— Four page-read buffers (each 128 bits wide) and a prefetch controller support speculative
reading and optimized flash access.
PXS20 Microcontroller Reference Manual, Rev. 1
1-8
Freescale Semiconductor