Chapter 8. DMA Controller
8-7
DMA Operation
8.3.3 DMA Operation Flow
Figure 8-2 shows a general flow diagram for the operation of the DMA controller on the
MPC8240.
Figure 8-2. DMA Controller General Flow
Save CDAR
Periodic mode
Timer Expires.
Restore CDAR
Chaining mode
Load the parameters
from memory into
the DMA registers
Load the contents of
NDAR into CDAR
Use the parameters
in the DMA registers
Read a line
*
of data
from memory (or PCI)
and decrement BCR
Write a line
*
of data
to memory (or PCI)
Direct mode
Done
Done
*
The first and/or last transfer will
be less than a line size transfer if
the initial address is not line
aligned and/or the byte count is
not an exact multiple of lines.
EOCA
BCR = 0
otherwise
Direct mode
otherwise
otherwise
EOTD = 1
otherwise
Periodic mode
EOSI
0
1
EOCAI
1
Содержание MPC8240
Страница 1: ...MPC8240UM D Rev 1 1 2001 MPC8240 Integrated Processor User s Manual ...
Страница 38: ...xviii MPC8240 Integrated Processor User s Manual TABLES Table Number Title Page Number ...
Страница 48: ...xlviii MPC8240 Integrated Processor User s Manual Acronyms and Abbreviations ...
Страница 312: ...6 94 MPC8240 Integrated Processor User s Manual ROM Flash Interface Operation ...
Страница 348: ...7 36 MPC8240 Integrated Processor User s Manual PCI Host and Agent Modes ...
Страница 372: ...8 24 MPC8240 Integrated Processor User s Manual DMA Register Descriptions ...
Страница 394: ...9 22 MPC8240 Integrated Processor User s Manual I2O Interface ...
Страница 412: ...10 18 MPC8240 Integrated Processor User s Manual Programming Guidelines ...
Страница 454: ...12 14 MPC8240 Integrated Processor User s Manual Internal Arbitration ...
Страница 466: ...13 12 MPC8240 Integrated Processor User s Manual Exception Latencies ...
Страница 516: ...16 14 Watchpoint Trigger Applications ...
Страница 538: ...B 16 MPC8240 Integrated Processor User s Manual Setting the Endian Mode of Operation ...
Страница 546: ...C 8 MPC8240 Integrated Processor User s Manual ...
Страница 640: ...INDEX Index 16 MPC8240 Integrated Processor User s Manual ...