Answers Database
XABEL 5.1/EPLD designs: FOE pins are active *high*
Record #543
Product Family: Software
Product Line: Data I/O
Product Part: xabel
Product Version: 5.1
Problem Title:
XABEL 5.1/EPLD designs: FOE pins are active *high*
Problem Description:
LONG DESCRIPTION:
PROBLEM:
Customer assigns a pin in XABEL/ABEL to a FOE (Fast Output Enable) pin, but
when the design is compiled, the pin assigned to the FOE pin is assigned to
a different pin.
Solution 1:
CAUSE:
The user defined in ABEL/XABEL code a FOE pin, but the FOE signal was
defined as active-low in the code.
SOLUTION:
The FOE are active high by architecture. The only way to get an active low
FOE is to reroute the signal through the AND-array and a macrocell. So, the
user must either allow this rerouting of the signal, or invert the FOE signal
outside of the device.
End of Record #543 - Last Modified: 12/22/95 09:59 |
