Answers Database

XABEL 5.0 and XC7000 EPLDS: The .D extension is not supported by PLUSASM


Record #424

Product Family:  Software

Product Line:  Data I/O

Problem Title:
XABEL 5.0 and XC7000 EPLDS: The .D extension is not supported by PLUSASM


Problem Description:
PROBLEM:

If the .D extension is used in XABEL and compiled to PLUSASM, it will
be ignored and the resulting equations will reference the registered
signal instead.  PLUSASM does not have an analog to the .D extension
and the XABEL compiler does not know how to handle it. The .D extension
cannot be used on the left-hand side of an equation. (This is pointed
out in the note at the bottom of page 7-11 of the XACT 5 X-Abel User
Guide).


Solution 1:


WORKAROUND:

The same result may be accomplished by declaring a
combinational signal signal_d to reference as the d input of the
registered signal and then declaring a seperate registered signal with
signal_q := signal_d.




End of Record #424