AR# 2959: Foundation Project Manager: Hierarchical, Error xr57 - Input signal drives more than one input buffer.
Foundation Project Manager: Hierarchical, Error xr57 - Input signal drives more than one input buffer.
Keywords: Error, xr57, input, pad, buffer, ext
Error xr57: Input pad signal 'signalname' drives more than one input buffer. A chip input can only drive 2 input signals when one drives a fast input and the other drives a non-fast input. Make sure that two input pad signals are not accidentally connected together.
A possible cause may be that a lower level (NON-TOP LEVEL) schematic is referred to in the Foundation Project Manager.
Additional EXT records are referenced by this lower sheet, thus causing for the above mentioned error message.
In the Foundation Project Manager, the following should appear: