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CPLD XC9500/XL : How are initial states of flip-flops determined on the 9500 CPLD's?
Record #3123
Problem Title:
CPLD XC9500/XL : How are initial states of flip-flops determined on the 9500 CPLD's?
Problem Description:
Urgency: Standard
General Description:
The user may want to have the powerup state of a flip flop to be a
logic high - `1`. What type of flip flop would have to be used in
order to achieve that? Is there a property that can be attached to
a flop to have it powerup into a `1` state?
Solution 1:
All flip flops will be initialized with a '0', but adding the attribute
INIT=S will allow any flip flop with this attribute to power up
in the `1` state.
Example:
You have a flip flop instance named TEST
In your UCF you would place
INST TEST INIT=S;
End of Record #3123 - Last Modified: 02/03/00 11:56 |
