EP80579 Datasheet, PDF (644/1916 Pages) Intel Corporation – Intel® EP80579 Integrated Processor Product Line

Intel^® EP80579 Integrated Processor
16.5.1.64 Offset 268h: DDRIOMC2 - DDR IO Mode Control Register 2
This register controls functionality of the DDRIO.
This CSR is in the memory-mapped IO region of Bus 0, Device 0, Function 0 of the
memory controller. The SMRBASE register described in Section 16.1.1.9, “Offset 14h:
SMRBASE - System Memory RCOMP Base Address Register” on page 395, provides the
base address for these registers. The offsets listed for the following registers are
relative to this base address.
The value for BAR for all registers in this section is BAR14h.
Acceptable values for legoverride[4:0] are 0-30d
Example(R_DQ, dynamic): Assume Rext = 249 ohms
R_DQ = Rext*2/(31-legoverride[4:0])
When legoverride[4:0] = 00000, R_DQ = (249*2)/(31-0) = 16.1 ohms
When legoverride[4:0] = 11110, R_DQ = (249*2)/(31-30) = 498 ohms
Table 16-289.Legoverride details
Mode (select via
legoverride[5:4])
Legoverride[9:6], [4:0]
static: legoverride[5:4] =
10b
[9:6] static impedance control
setting of CMD/ADD/CLK
[3:0] static impedance control
setting of DQ/DM/DQS
[9:6] dynamic impedance control
setting of CMD/ADD/CLK
dynamic: legoverride[5] =
0b
[4:0] dynamic impedance control
setting of DQ/DM/DQS
Details
See gray code below (valid for 1 to 10)
See gray code below (valid for 1 to 10)
R_CA = R_DQ * 6.154 / Legoveride[9:6] or
R_min_CA (Ohm)
Where, Rext is the external R connected to
DDR_DRVCRES pin and Rmin is impedance
when all the driver legs are selected. Rmin
is process/voltage/temp dependent.
R_DQ = Rext*2 / (31- Legoverride[3:0]) or
R_min_DQ (Ohm)
Where, Rext is the external R connected to
DDR_DRVCRES pin and Rmin is impedance
when all the driver legs are selected. Rmin
is process/voltage/temp dependent.
Table 16-290.Legoverride - Gray code
CSR value for
static impedance
control (binary)
Desired value for
impedance control
(Decimal)
1000
15
1001
14
1011
13
1010
12
1110
11
1111
10
1101
9
Intel^® EP80579 Integrated Processor Product Line Datasheet
644
August 2009
Order Number: 320066-003US