＜Error Message >
Error (176202): The differential I/O standard <name> cannot be used on the pin <name>, because the specified pin uses a tri- The differential I/O standard <name> cannot be used on the pin <name>, because the specified pin uses a tri- output buffer.
Tri-state cannot be used on the differential pins of the Cyclone® IV.
" Differential HSTL-18", not "HSTL-18", to achieve tri-state by providing a p-side and n-side.
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Category: Specifications
Tool: Quartus® Prime
Device: Cyclone® IV