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Registers
421
SPRUH82C – April 2013 – Revised September 2016
Copyright © 2013–2016, Texas Instruments Incorporated
DDR2/mDDR Memory Controller
14.4.17 DDR PHY Control Register (DRPYC1R)
The DDR PHY control register 1 (DRPYC1R) configures the DDR2/mDDR memory controller read latency.
The DRPYC1R is shown in
and described in
.
Figure 14-37. DDR PHY Control Register 1 (DRPYC1R)
31
16
Reserved
R-0
15
14
12
11
8
7
6
5
3
2
0
Rsvd
CONFIG_DLL_MODE
Reserved
EXT_STRBEN
PWRDNEN
Reserved
RL
R-0
R/W-0
R-0
R/W-0
R/W-1
R-0
R/W-6h
LEGEND: R/W = Read/Write; R = Read only; -
n
= value after reset
Table 14-41. DDR PHY Control Register 1 (DRPYC1R) Field Descriptions
Bit
Field
Value
Description
31-15
Reserved
0
Reserved
14-12
CONFIG_DLL_MODE
DLL configuration. Controls the value assigned to the config_dll_mode input.
0-1h
DLL REFCLK is enabled.
2h
DLL REFCLK is disabled.
3h-7h
Reserved
11-8
Reserved
0
Reserved
7
EXT_STRBEN
Internal/External strobe gating.
0
Internal strobe gating mode.
1
External strobe gating mode.
6
PWRDNEN
Power down receivers.
0
Receivers powered up when idle.
1
Receivers powered down when idle.
5-3
Reserved
0
Reserved
2-0
RL
0-7h
Read latency. Read latency is equal to CAS latency plus round trip board delay for data
minus 1. The maximum value of read latency that is supported is CAS latency plus 2. The
minimum read latency value that is supported is CAS latency plus 1. The read latency value
is defined in number of MCLK/DDR_CLK cycles.