IOSTANDARD Attribute
The IOSTANDARD attribute is available to choose the values for an I/O standard for all I/O buffers. The supported I/O standards are listed in the XP IOB Supported Standards section. The IOSTANDARD attribute uses the following syntax in the XDC file:set_property IOSTANDARD value [get_ports port_name]
DRIVE Strength Control
LVCMOS drivers (LVCMOS12 and LVCMOS15) drivers support output drive strength control to size the driver output strength to the load driven. For a list of drive options and standards, see the XP IOB Supported Standards section. Assigning the DRIVE property 2, 4, 6, 8, or 12 (LVCMOS15 only) ensures that the XP IOB driver can meet valid logic thresholds for loads of 2 mA, 4 mA, 6 mA, 8 mA, or 12 mA, respectively. The DRIVE attribute uses the following syntax in the XDC file:
set_property DRIVE value [get_ports port_name]SLEW Control
Most drivers support FAST, MEDIUM, and SLOW slew-rate options. These options can be used to optimize the edge rate of the driver for specific applications. For a list of IOSTANDARDS that support slew control, see the XP IOB Supported Standards section.
set_property SLEW value [get_ports port_name]VOH Attribute
MIPI_DPHY, LVSTL_11, and DIFF_LVSTL_11 support the VOH attribute to help define the mode of the driver. VOH helps define the desired output High level for the driver. This can be used to define the use mode for a given standard. For LVSTL_11 and DIFF_LVSTL_11, the VOH attribute must be 50 (50% of VCCO). For MIPI_DPHY, the VOH attribute must be 28 (28% of VCCO). For scenarios where an SSTL15 driver needs to drive a 1.8V SSTL receiver, a VOH attribute of 80 adjusts the SSTL15 driver to be compatible with a 1.8V SSTL receiver. This option is limited in its scope to a single VOH option for a given standard. If not set, this property defaults to the appropriate VOH level.set_property VOH value [get_ports port_name]