Answers Database
Viewlogic Simulation: Forcing a value to a signal and then releasing will cancel any FLOATVAL attributes
Record #110
Product Family: Software
Product Line: ViewLogic
Product Part: PROsim
Problem Title:
Viewlogic Simulation: Forcing a value to a signal and then releasing will cancel any
FLOATVAL attributes
Problem Description:
Solution 1:
When simulating a design, if a node that has a FLOATVAL attribute is forced
and then released, the FLOATVAL value will not be restored. Once released, the
node will go to high impedance.
For example, the global set/reset signal for the XC4000 family of devices known
as GSR has a FLOATVAL=0. Before asserting GSR, and after simulating for some
amount of time, GSR will take on the FLOATVAL value of '0'. Once GSR is asserted
to '1', if it is released using the 'r' command, it will take on the value of 'Z'.
Because this value is unacceptable, GSR must be driven Low to de-assert it so that
it takes on the value of '0'.
End of Record #110 - Last Modified: 12/11/95 12:02 |
