Input Port CALCLK Not Driven by the Same Source when Compiling Serial Digital Interface Design - Input Port CALCLK Not Driven by the Same Source when Compiling Serial Digital Interface Design Description Fitter error occurs when compiling the serial digital interface (SDI) I transmitter only with the Cyclone V device. The error message "Input Port CALCLK must be driven by the same source" is displayed. This issue affects the Cyclone V device in 12.1. Resolution There is no workaround for this issue. This issue is fixed in 12.1sp1dp1. Custom Fields values: ['novalue'] Troubleshooting novalue True ['novalue'] ['FPGA Dev Tools Quartus II Software'] 12.1.1 12.1 ['Cyclone® V FPGAs and SoCs'] ['novalue'] ['novalue'] ['novalue']