External Memory Controller (EMC)
Symphony DSP56724/DSP56725 Multi-Core Audio Processors, Rev. 0
Freescale Semiconductor
21-61
Figure 21-19. CL = 2 (2 Clock Cycles)
21.4.3.7.4
Last-Data-In-to-Precharge—Write Recovery
The Last-Data-In-to-Precharge parameter, controlled by SDMR[WRC], defines the earliest timing for a
PRECHARGE command after the last data was written to the SDRAM.
Figure 21-20. WRC = 2 (2 Clock Cycles)
21.4.3.7.5
Refresh Recovery Interval (RFRC)
The Refresh Recovery Interval parameter, controlled by SDMR[RFRC], defines the earliest timing for an
ACTIVATE or REFRESH command after a REFRESH command to the same SDRAM device.
Figure 21-21. RFRC = 4 (6 Clock Cycles)
1111
0000
1111
ZZZZZZZZ
RAS ADD
ZZZZZZZZ
CAS_ADD
D0
D1
D2
LCLK
LALE
LCSx
LSDRAS
LSDCAS
LSDWE
LSDDQM
LAD[23:0]
D3
XXXX
CL = 2
READ
Command
First Data Out
1111
0000
1111
ZZZZZZZZ
CAS ADD
D0
RAS ADD
CAS ADD
LCLK
LALE
LCSx
LSDRAS
LSDCAS
LSDWE
LSDDQM
LAD[23:0]
D1
D2
D3
X
0000
D0
D1
WRC = 2
Last Data In
PRECHARGE
Command
WRITE
Command
1111
ZZZZZZZZ
RAS ADD
XXXX
CAS ADD
LCLK
LALE
LCSx
LSDRAS
LSDCAS
LSDWE
LSDDQM
LAD[23:0]
RFRC = 4 (6 clocks)
AUTO REFRESH
Command
ACTIVATE
Command
PRECHARGE ALL
Command (if needed)
PRETOACT = 3
Содержание Symphony DSP56724
Страница 22: ...Symphony DSP56724 DSP56725 Multi Core Audio Processors Rev 0 1 10 Freescale Semiconductor Introduction ...
Страница 52: ...Symphony DSP56724 DSP56725 Multi Core Audio Processors Rev 0 2 30 Freescale Semiconductor Signal Descriptions ...
Страница 112: ...Symphony DSP56724 DSP56725 Multi Core Audio Processors Rev 0 7 12 Freescale Semiconductor Clock Generation Module CGM ...
Страница 244: ...Symphony DSP56724 DSP56725 Multi Core Audio Processors Rev 0 14 6 Freescale Semiconductor Shared Bus Arbiter ...
Страница 246: ...Symphony DSP56724 DSP56725 Multi Core Audio Processors Rev 0 15 2 Freescale Semiconductor Shared Memory Shared Memory ...