Historically we have provided three mechanisms for defining some form of constant or default values for a pin/net in XJDeveloper. These are BSDL compliance pins, bus disable values and constant pins, which allow you to define pins which XJTAG should keep in a constant state during automated testing, such as with Connection Test. However these approaches are profile- and subchain-agnostic.
From XJTAG 3.11, for situations where more control is required over when and in which profiles a value is applied we now allow these default values to be set and cleared from XJEase. These XJEase default values will override any pre-existing constant pin or bus disable values, and exist until the current XJEase runtime exits (they do not persist between test runs). This new functionality may be used in device, include and circuit code files.
These values are set using the new SET_DEFAULT_OVERRIDE function, which takes a comma separated list of default override pairs, each with a pin reference string and a value assignment, for example:
The four allowed values are 1 (high), 0 (low), I (input) and DEFAULT_NONE. Setting a pin to the last value effectively removes any existing constant pin, disable or compliance values in the current runtime. XJEase will attempt to apply the given value when the statement executes, producing a runtime warning if it is unable to do so. For projects with multiple boards the board name may be required to properly resolve the pin references. Any unresolved references produce syntax warnings in the project.
Calling RESET_DEFAULT_OVERRIDE will remove any previously set XJEase default overrides (including restoring any which were removed by using the value DEFAULT_NONE). This function takes a comma separated list of pin reference strings, such as:
More details of these features can be found in the Help files installed with your XJTAG system.
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