Specifications

Embedded System Tools Guide (EDK 6.2i) www.xilinx.com 253
UG111 (v1.4) January 30, 2004 1-800-255-7778
Port
R
Where edge_value is either RISING or FALLING.
ENABLE
Tri-state signals can have multi-bit enable control, or a single bit enable control on the bus.
This is specified with the ENABLE keyword.
Format
PORT mysignal = “”, DIR=IO, VEC=[0:31], ENABLE=enable_value
Where enable_value is either SINGLE or MULTI. If there is no specification, then
SINGLE is the default value.
Please see the “Design Considerations” section about designing tri-state signals at the
HDL level.
ENDIAN
The endianess of a signal is specified by the ENDIAN keyword.
Format
PORT mysignal = “”, DIR=I, VEC=[A:B], ENDIAN=endian_value
Where endian_value is either BIG or LITTLE. If there is no specification, then BIG is the
default value. Where A and B are positive integer expressions.
GUI_PERMIT
The GUI_PERMIT keyword defines GUI usage level of a parameter. Currently,
unsupported.
Format
PORT CLK="", DIR=I, GUI_PERMIT=ALL_USERS
The following table lists GUI_PERMIT values:
INTERRUPT_PRIORITY
The INTERRUPT_PRIORITY keyword defines the relative priority of interrupt signals.
Format
PORT Intr="", DIR=O, SENSITIVITY=EDGE_RISING, SIGIS=INTERRUPT, INTERRUPT_PRIORITY=LOW
Table 16-18: GUI_PERMIT Values
GUI_PERMIT Definition
ADVANCED_USER EDK GUI tools do not display
ALL_USERS EDK GUI tools ask user to set a value
DISPLAYONLY EDK GUI tools display to user, however, does not allow user to
modify or add to MHS
NONE EDK GUI tools do not display to user. However, if user adds
parameter in MHS text mode which have value NONE, then
EDK GUI tools will s display and allow users to modify value.