MPC563XM Reference Manual, Rev. 1
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Freescale Semiconductor
Preliminary—Subject to Change Without Notice
support zero-wait responses. Normal Flash array accesses (i.e. those accesses that do not hit in the prefetch
buffers) are registered in the FBIU and are forwarded to the system bus on the following cycle, incurring
at least one wait states (depending on the frequency).
The Flash memory block is arranged as two functional units, the first being the Flash core. The Flash core
is composed of arrayed non-volatile storage elements, sense amplifiers, row selects, column selects, charge
pumps, ECC logic and redundancy logic. The arrayed storage elements in the Flash core are subdivided
into physically separate units referred to as blocks.
The second functional unit of Flash memory is the memory interface (MI). The MI contains the registers
and logic that control the operation of the Flash core. The MI is also the interface between the Flash
module and the FBIU. The FBIU connects the MCU system bus to the Flash module, and provides all
system level customization and configuration functionality.
The CFlash does not support RWW within its sectors. But RWW (read-while-write) is supported between
partitions.
11.4
Features
11.4.1
FBIU features
The following list summarizes the key features of the FBIU:
•
The FBIU system bus interface supports a 32-bit data bus. All byte, halfword, and word reads are
supported. Only aligned word writes are supported.
•
The Flash array interface supports a 128-bit read data bus and a 32-bit write data bus.
•
The FBIU provides configurable read buffering and line prefetch support. Four line read buffers
(each 128 bits wide) and a prefetch controller are used to support single-cycle read responses (zero
wait-states) for hits in the buffers.
•
The FBIU provides hardware and software configurable read and write access protections on a
per-master basis.
•
The FBIU allows configurable access timing.
•
The FBIU provides multiple-mapping support and mapping-based block access timing allowing
use for emulation of other memory types.
11.4.2
Flash memory array features
The Flash memory array has the following features:
•
Software programmable block program/erase restriction control for low, mid, and high address
spaces
•
Erase of selected blocks
•
ECC with single-bit correction, double-bit detection
•
Embedded hardware program and erase algorithm
•
Read-while-write with multiple partitions
•
Stop mode for low power stand-by