MSC8144E Reference Manual, Rev. 3
12-40
Freescale
Semiconductor
DDR SDRAM Memory Controller
12.7.6
DDR SDRAM Timing Configuration Register 2 (TIMING_CFG_2)
TIMING_CFG_2 sets the clock delay to data for writes and should be defined according to the
system timing.
ACTTOACT
6–4
0
Activate-to-Activate Interval (t
RRD
)
Specifies the minimum number of clock cycles between an
activate command and another activate command for a different
logical bank in the same physical bank (chip select). The default
is one clock cycle. This interval is calculated from the AC
specifications of the SDRAM.
This field must be programmed for proper operation of the DDR
Controller.
000
Reserved.
001
1 clock cycle.
010
2 clock cycles.
011
3 clock cycles.
100
4 clock cycles.
101
5 clock cycles.
110
6 clock cycles.
111
7 clock cycles.
—
3
0
Reserved. Write to zero for future compatibility.
WRTORD
2–0
0
Last Write Data Pair to Read Command Interval ( t
WTR
)
Specifies the minimum number of clock cycles between the last
write data pair and the subsequent read command to the same
physical bank.
This field must be programmed for proper operation of the DDR
Controller.
000
Reserved.
001
1 clock cycle.
010
2 clock cycles.
011
3 clock cycles.
100
4 clock cycles.
101
5 clock cycles.
110
6 clock cycles.
111
7 clock cycles.
TIMING_CFG_2
DDR SDRAM Timing Configuration Register 2
Offset 0x010C
Bit
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
16
—
ALL
CPO
—
WR_LAT
—
Type
R
R/W
R
R/W
R
Reset
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Bit
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
RD_TO_PRE
WRITE_DATA_
DELAY
—
CKE_PLS
FOUR_ACT
Type
R/W
R
R/W
Reset
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Table 12-21. TIMING_CFG_2 Bit Descriptions
Bit
Reset Description
Settings
0
—
Reserved. Write to zero for future compatibility.
ALL
30–28
0
Additive Latency
The additive latency must be set to a value less than
TIMING_CFG_1[ACTTORW].
This timing parameters applies to DDR2 only
000
0 clock cycles.
001
1 clock cycle.
010
2 clock cycles.
011
3 clock cycles.
100
4 clock cycles.
101
5 clock cycles.
110–111 Reserved.
Table 12-20. TIMING_CFG_1 Field Descriptions (Continued)
Bits
Reset
Description
Settings
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 ...