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MPC8240 Integrated Processor User’s Manual
FPM or EDO DRAM Interface Operation
6.3.11.2 DRAM Self-Refresh in Sleep Mode
The MPC8240 allows the system designer to use DRAMs that provide self refresh for
power-down situations. These DRAMs should be used if data retention is imperative during
sleep mode. The MPC8240 properly configures these DRAMs during sleep mode if the
appropriate configuration register bit is set. The timing for such a self refresh initiation is
shown in Figure 6-45.
Figure 6-45. DRAM Self-Refresh Timing Configuration
Table 6-25. FPM or EDO DRAM Power Saving Modes Refresh Configuration
Power
Saving
Mode
Refresh
Type
Power Management Control Register (PMCR1)
MCCR1
[SREN]
PM
DOZE
NAP
SLEEP
LP_REF_EN
Doze
Normal
1
1
0
0
—
—
Nap
Normal
1
—
1
0
—
—
Sleep
Self
1
—
—
1
1
1
Normal
1
—
—
1
1
0
None
1
—
—
1
0
—
MCLK
RAS[0,7]
RAS[1,6]
RAS[2,5]
RAS[3,4]
CAS[0:7]
CSR
RPC
WE
INTERNAL
HI-Z
RASS
20 cycles
DATA BUS
NOTE: RASS = Self-refresh interval (must be greater
than 100 µs).
CHS
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 ...