9-22
MCF5272 User’s Manual
SDRAM Interface
Figure 9-13. SDRAM Refresh Cycle
Figure 9-14 shows the timing for entering SDRAM self-refresh mode. During a
PRECHARGE
ALL
command (T1), the SDRAM writes all of its on-chip RAM page buffers
back into the SDRAM array. The SDTR[RP] value determines the number of dead cycles
after a precharge. Note that auto refresh occurs in T3. SDTR[RC] determines the number
of clock cycles the SDRAM remains in refresh state, during which time it cannot accept
other commands.
T0
T1
T2
T3
T4
T5
T6
T7
T8
T9
SDCLK
SDADR[13:0]
A10_PRECHG
SDBA[1:0]
SDCS
RAS0
SDWE
Precharge
All Banks
NOP
Auto
Refresh
CAS0
SDCLKE
(H)
Next Command
t
RC
Содержание DigitalDNA ColdFire MCF5272
Страница 1: ...MCF5272UM D Rev 0 02 2001 MCF5272 ColdFire Integrated Microprocessor User s Manual ...
Страница 38: ...xxxviii MCF5272 User s Manual TABLES Table Number Title Page Number ...
Страница 58: ...1 10 MCF5272 User s Manual MCF5272 Specific Features ...
Страница 90: ...2 42 MCF5272 User s Manual Exception Processing Overview ...
Страница 96: ...3 6 MCF5272 User s Manual MAC Instruction Execution Timings ...
Страница 158: ...5 46 MCF5272 User s Manual Motorola Recommended BDM Pinout ...
Страница 184: ...7 12 MCF5272 User s Manual Interrupt Controller Registers ...
Страница 338: ...13 44 MCF5272 User s Manual Application Examples ...
Страница 414: ...18 6 MCF5272 User s Manual PWM Programming Model ...
Страница 452: ...19 38 MCF5272 User s Manual Power Supply Pins ...
Страница 482: ...20 30 MCF5272 User s Manual Reset Operation ...
Страница 492: ...21 10 MCF5272 User s Manual Non IEEE 1149 1 Operation ...
Страница 548: ...INDEX Index 12 MCF5272 User s Manual ...