8-4
MCF5282 User’s Manual
MOTOROLA
Register Descriptions
8.4.2
Memory Base Address Register (RAMBAR)
The MCF5282 supports dual-ported local SRAM memory. This processor-local memory
can be accessed directly by the core and/or other system bus masters. Since this memory
provides single-cycle accesses at processor speed, it is ideal for applications where
double-buffer schemes can be used to maximize system-level performance. For example, a
DMA channel in a typical double-buffer (also known as a ping-pong scheme) application
may load data into one portion of the dual-ported SRAM while the processor is
manipulating data in another portion of the SRAM. Once the processor completes the data
calculations, it begins processing the just-loaded buffer while the DMA moves out the
just-calculated data from the other buffer, and reloads the next data block into the just-freed
memory region. The process repeats with the processor and the DMA “ping-ponging”
between alternate regions of the dual-ported SRAM.
The MCF5282 design implements the dual-ported SRAM in the memory space defined by
the RAMBAR register. There are two physical copies of the RAMBAR register: one
located in the processor core and accessible only via the privileged MOVEC instruction at
CPU space address 0xC05, and another located in the SCM at 0x008. ColdFire
core accesses to this memory are controlled by the processor-local copy of the RAMBAR,
while module accesses are enabled by the SCM's RAMBAR.
31
30
29
16
Field BA31 BA30
—
Reset
0
1
—
R/W
R/W
15
1
0
Field
—
V
Reset
—
R/W
R/W
Address
0x000
Figure 8-1. IPS Base Address Register (IPSBAR)
Table 8-2. IPSBAR Field Description
Bits
Name
Description
31–30
BA
Base address. Defines the base address of the 1-Gbyte internal peripheral space. This is the
starting address for the IPS registers when the valid bit is set.
29–1
—
Reserved, should be cleared.
0
V
Valid. Enables/disables the IPS Base address region. V is set at reset.
0 IPS Base address is not valid.
1 IPS Base address is valid.
Содержание ColdFire MCF5281
Страница 1: ...MCF5282UM D Rev 2 1 2004 MCF5282 ColdFire Microcontroller User s Manual Devices Supported MCF5281 ...
Страница 124: ...3 20 MCF5282 User s Manual MOTOROLA EMAC Instruction Set Summary ...
Страница 141: ...MOTOROLA Chapter 5 Static RAM SRAM 5 5 SRAM Programming Model ...
Страница 142: ...5 6 MCF5282 User s Manual MOTOROLA SRAM Programming Model ...
Страница 168: ...6 26 MCF5282 User s Manual MOTOROLA Interrupts ...
Страница 186: ...7 18 MCF5282 User s Manual MOTOROLA Functional Description ...
Страница 228: ...9 22 MCF5282 User s Manual MOTOROLA Functional Description ...
Страница 246: ...10 18 MCF5282 User s Manual MOTOROLA Low Power Wakeup Operation ...
Страница 254: ...11 8 MCF5282 User s Manual MOTOROLA Memory Map and Registers ...
Страница 264: ...12 10 MCF5282 User s Manual MOTOROLA Chip Select Registers ...
Страница 280: ...13 16 MCF5282 User s Manual MOTOROLA Misaligned Operands ...
Страница 314: ...14 34 MCF5282 User s Manual MOTOROLA MCF5282 External Signals ...
Страница 339: ...MOTOROLA Chapter 15 Synchronous DRAM Controller Module 15 25 SDRAM Example ...
Страница 340: ...15 26 MCF5282 User s Manual MOTOROLA SDRAM Example ...
Страница 356: ...16 16 MCF5282 User s Manual MOTOROLA DMA Controller Module Functional Description ...
Страница 408: ...17 52 MCF5282 User s Manual MOTOROLA Buffer Descriptors ...
Страница 446: ...20 24 MCF5282 User s Manual MOTOROLA Interrupts ...
Страница 474: ...22 18 MCF5282 User s Manual MOTOROLA Programming Model ...
Страница 510: ...23 36 MCF5282 User s Manual MOTOROLA Operation ...
Страница 526: ...24 16 MCF5282 User s Manual MOTOROLA I2C Programming Examples ...
Страница 672: ...28 12 MCF5282 User s Manual MOTOROLA Functional Description ...
Страница 718: ...29 46 MCF5282 User s Manual MOTOROLA Motorola Recommended BDM Pinout ...
Страница 750: ...32 8 MCF5282 User s Manual MOTOROLA Ordering Information ...
Страница 800: ...A 22 MCF5282 User s Manual MOTOROLA ...