CONTROL_MODULE Registers
Table 9-101. ddr_data0_ioctrl Register Field Descriptions (continued)
Bit
Field
Type
Reset
Description
19
io_config_wd0_dqs
R/W
0h
Input that selects pullup or pulldown for DDR_DQS0 and
DDR_DQSn0.
Used with io_config_wd1_dqs to define pullup/pulldown according to
the following:
WD1:WD0
00b: Pullup/Pulldown disabled for both DDR_DQS0 and
DDR_DQSn0
01b: Enable weak pullup for DDR_DQS0 and weak pulldown for
DDR_DQSn0
10b: Enable weak pulldown for DDR_DQS0 and weak pullup for
DDR_DQSn0
11b: Weak keeper enabled for both DDR_DQS0 and DDR_DQSn0
18
io_config_wd0_dm
R/W
0h
Input that selects pullup or pulldown for DM.
Used with io_config_wd1_dm to define pullup/pulldown according to
the following:
WD1:WD0
00: Pullup/Pulldown disabled
01: Weak pullup enabled
10: Weak pulldown enabled
11: Weak keeper enabled
17-10
io_config_wd0_dq
R/W
0h
Input that selects pullup or pulldown for DQ.
There are 2 bits per IO: io_config_wd1_dq and io_config_wd0_dq.
For example:
macro pin 0: WD1 is bit 20, WD0 is bit 10
macro pin 1: WD1 is bit 21, WD0 is bit 11
...
macro pin 7: WD1 is bit 27, WD0 is bit 17
See the DDR PHY to IO Pin Mapping table in the Control Module
Functional Description section for a mapping of macro bits to I/Os.
WD1:WD0
00: Pullup/Pulldown disabled
01: Weak pullup enabled
10: Weak pulldown enabled
11: Weak keeper enabled
9-8
io_config_sr_clk
R/W
0h
2 bit to program clock IO Pads (DDR_DQS/DDR_DQSn) output slew
rate.
These connect as SR1, SR0 of the corresponding IO buffer.
See the DDR Slew Rate Control Settings table in the Control Module
Functional Description section for a definition of these bits.
7-5
io_config_i_clk
R/W
0h
3-bit configuration input to program clock IO pads
(DDR_DQS/DDR_DQSn) output impedance.
These connect as I2, I1, I0 of the corresponding buffer.
See the DDR Impedance Control Settings table in the Control
Module Functional Description section for a definition of these bits.
4-3
io_config_sr
R/W
0h
2 bit to program data IO Pads output slew rate.
These connect as SR1, SR0 of the corresponding IO buffer.
See the DDR Slew Rate Control Settings table in the Control Module
Functional Description section for a definition of these bits.
2-0
io_config_i
R/W
0h
3-bit configuration input to program data IO output impedance.
These connect as I2, I1, I0 of the corresponding IO buffer.
See the DDR Impedance Control Settings table in the Control
Module Functional Description section for a definition of these bits.
860
Control Module
SPRUH73H – October 2011 – Revised April 2013
Copyright © 2011–2013, Texas Instruments Incorporated