MSC8144E Reference Manual, Rev. 3
12-14
Freescale
Semiconductor
DDR SDRAM Memory Controller
Figure 12-5 through Figure 12-7 show DDR SDRAM timing for various types of accesses,
including a single-beat read, a single-beat write, and a burst-write. Note that all signal transitions
occur on the rising edge of the memory bus clock and that single-beat read operations are
identical to burst-reads. These figures assume that DDR_SDRAM_CLK_CNTL[CLKADJ] =
0100 (set to 1/2 DRAM cycle), the additive latency is 0 DRAM cycles, and the write latency is 1
DRAM cycle (for DDR1).
ar
Figure 12-5. DDR SDRAM Burst Read Timing: ACTTORW = 3,
MCAS
Latency = 2
Figure 12-6. DDR SDRAM Single-Beat (Word) Write Timing: ACTTORW = 3
ACTTORW
ROW
COL
SDRAM Clock
MCS
MCAS
MA[15–0]
MDQ[0–31]
MWE
MRAS
MDQS
COL
D1 D2 D3
D1 D2
D0
D3
D0
0
1
2
3
4
5
6
7
8
9
10
11
12
CASLAT
ACTTORW
ROW
COL
SDRAM Clock
MCS
MCAS
MA[15–0]
MDQ[0–31]
MWE
MRAS
MDQS
D0 D1 D2 D3
0
MDM[0–3]
WRREC
A10=0
PRECHARGE
PRETOACT
ROW
0
1
2
3
4
5
6
7
8
9
10
11
12
F
F
F
Summary of Contents for MSC8144E
Page 1: ...MSC8144E Reference Manual Quad Core Media Signal Processor MSC8144ERM Rev 3 July 2009 ...
Page 48: ...MSC8144E Reference Manual Rev 3 xlviii Freescale Semiconductor ...
Page 86: ...MSC8144E Reference Manual Rev 3 1 38 Freescale Semiconductor Overview ...
Page 168: ...MSC8144E Reference Manual Rev 3 3 60 Freescale Semiconductor External Signals ...
Page 242: ...MSC8144E Reference Manual Rev 3 5 26 Freescale Semiconductor Reset ...
Page 314: ...MSC8144E Reference Manual Rev 3 8 24 Freescale Semiconductor General Configuration Registers ...
Page 414: ...MSC8144E Reference Manual Rev 3 10 14 Freescale Semiconductor MSC8144E SC3400 DSP Subsystem ...
Page 452: ...MSC8144E Reference Manual Rev 3 11 38 Freescale Semiconductor Internal Memory Subsystem ...
Page 520: ...MSC8144E Reference Manual Rev 3 12 68 Freescale Semiconductor DDR SDRAM Memory Controller ...
Page 1070: ...MSC8144E Reference Manual Rev 3 21 28 Freescale Semiconductor Timers ...