This Figure shows a sample circuit illustrating a termination technique for differential POD (1.0V, 1.2V) with unidirectional termination and with matched driver and receiver termination values. In a specific circuit, all drivers and receivers must be at the same voltage level (1.2V or 1.0V); they are not interchangeable (i.e., DIFF_POD12 should only interface with DIFF_POD12).
This Figure shows a sample circuit illustrating a termination technique for differential POD (1.0V or 1.2V) with bidirectional termination and with matched driver and receiver termination values. In a specific circuit, all drivers and receivers must be at the same voltage level (1.0V or 1.2V); they are not interchangeable (i.e., DIFF_POD10_DCI should only interface with DIFF_POD10_DCI).
Table: POD Allowed Attributes lists the allowed attributes for POD I/O standards. Support is implied for primitives that are derivatives of the primitives listed in Table: POD Allowed Attributes (for example: *_DIFF_OUT, *_DCIEN, *_IBUFDISABLE, or *_INTERMDISABLE). Refer to the SelectIO Interface Primitives section for all supported derivatives.
Attributes |
IBUF/IBUFE3/IBUFDS/ |
OBUF/OBUFT |
IOBUF/IOBUFE3/IOBUFDS/ |
|||
---|---|---|---|---|---|---|
HP I/O |
HP I/O |
HP I/O |
||||
Allowed Values |
Default |
Allowed Values |
Default |
Allowed Values |
Default |
|
IOSTANDARD |
POD10 |
POD10 |
POD10 |
|||
SLEW |
N/A |
FAST |
SLOW |
FAST |
SLOW |
|
DQS_BIAS(5) |
TRUE |
FALSE |
N/A |
TRUE |
FALSE |
|
ODT |
RTT_40, RTT_48 |
RTT_NONE |
N/A |
RTT_40, RTT_48 |
RTT_NONE |
|
OUTPUT_ |
N/A |
RDRV_40_40 |
RDRV_40_40 |
RDRV_40_40 |
RDRV_40_40 |
|
IOSTANDARD |
POD10_DCI |
POD10_DCI |
POD10_DCI |
|||
SLEW |
N/A |
FAST |
SLOW |
FAST |
SLOW |
|
DQS_BIAS(5) |
TRUE |
FALSE |
N/A |
TRUE |
FALSE |
|
ODT |
RTT_40 |
RTT_40 |
N/A |
RTT_40 |
||
OUTPUT_ |
N/A |
RDRV_40_40 |
RDRV_40_40 |
RDRV_40_40 |
RDRV_40_40 |
|
IOSTANDARD |
POD12 |
POD12 |
POD12 |
|||
SLEW |
N/A |
FAST |
SLOW |
FAST |
SLOW |
|
PRE_EMPHASIS |
N/A |
RDRV_240 |
RDRV_NONE |
RDRV_240 RDRV_NONE(3) |
RDRV_NONE |
|
EQUALIZATION |
EQ_LEVEL0, EQ_LEVEL1, |
EQ_NONE |
N/A |
EQ_LEVEL0, EQ_LEVEL1, |
EQ_NONE |
|
OFFSET_CNTRL |
CNTRL_NONE |
CNTRL_NONE |
N/A |
CNTRL_NONE |
CNTRL_NONE |
|
DQS_BIAS(5) |
TRUE |
FALSE |
N/A |
TRUE |
FALSE |
|
ODT |
RTT_40 |
RTT_NONE |
N/A |
RTT_40 |
RTT_NONE |
|
OUTPUT_ |
N/A |
RDRV_40_40 |
RDRV_40_40 |
RDRV_40_40 |
RDRV_40_40 |
|
IOSTANDARD |
POD12_DCI |
POD12_DCI |
POD12_DCI |
|||
SLEW |
N/A |
FAST |
SLOW |
FAST |
SLOW |
|
PRE_EMPHASIS(6) |
N/A |
RDRV_240 RDRV_NONE(4) |
RDRV_NONE |
RDRV_240 RDRV_NONE(3) |
RDRV_NONE |
|
EQUALIZATION |
EQ_LEVEL0, EQ_LEVEL1, |
EQ_NONE |
N/A |
EQ_LEVEL0, EQ_LEVEL1, |
EQ_NONE |
|
OFFSET_CNTRL |
CNTRL_NONE |
CNTRL_NONE |
N/A |
CNTRL_NONE |
CNTRL_NONE |
|
TRUE |
FALSE |
N/A |
TRUE |
FALSE |
||
ODT |
RTT_40 |
RTT_40 |
N/A |
RTT_40 |
||
OUTPUT_ |
N/A |
RDRV_40_40 |
RDRV_40_40 |
RDRV_40_40 |
RDRV_40_40 |
|
Notes: 1.The allowed bidirectional configuration combinations for driver output impedance (OUTPUT_IMPEDANCE) and ODT are listed in Table: Only Allowed Combinations for Bidirectional Configurations . 2.ODT = RTT_NONE is not a valid setting for DCI I/O standards. 3.The allowed bidirectional configuration combinations for driver output impedance (OUTPUT_IMPEDANCE), ODT, and PRE_EMPHASIS are listed in Table: Allowed Combinations of OUTPUT_IMPEDANCE, ODT, and PRE_EMPHASIS . 4.The combinations allowed of driver output impedance (OUTPUT_IMPEDANCE) and PRE_EMPHASIS are listed in Table: Allowed Combinations of OUTPUT_IMPEDANCE and PRE_EMPHASIS . 5.Only applicable to DIFF_POD I/O standards. 6.This attribute has to be used in conjunction with ENABLE_PRE_EMPHASIS to enable the pre-emphasis function. 7.This is read-only on the primitive. The DQS_BIAS attribute is set on the I/O port rather than the primitive. |
Table: Allowed Combinations of OUTPUT_IMPEDANCE, ODT, and PRE_EMPHASIS and Table: Allowed Combinations of OUTPUT_IMPEDANCE and PRE_EMPHASIS lists the allowed combinations of attributes for POD I/O standards.