ITB clock lines -- clk share between blocks : How ?

Hello,

You want the reference clock that feeds the REFCLK_R5 input to be shared by the QR0 and QR2 GXB blocks ?

Indeed, it is feasible as long as the GXB blocks are located on the same side of the device.

As ITB lines are internal clock paths, you don't have to route any external trace on your PCB. The connection is done by the Quartus fitter, this is just a matter of gateware writing.

If you are instantiating GXB RX-Only blocks, you simply have to tie together their "rx_cruclk" inputs together and to connect them to your reference clock input pin.

If you are instantiating GXB TX&RX blocks, you can either use the "rx_cruclk" inputs as previously or use their "pll_inclk" inputs depending on which parts of the transceivers you want to synchronize.