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Altera_Forum
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13 years ago

Dedicated clock pin feeding lvds_rx ip ?

Hi, Is it possible to use a clock dedicated input pin in lvds standard to feed a lvds_rx rx_in pin ? I have this error in quartus (11.0 sp1): Error: Can't place pin "clkoutP" with an I/O re...
Altera_Forum's avatar
Altera_Forum
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13 years ago

This sounds like a Quartus bug, because Cyclone III hasn't input registers at all. As the device manual clarifies, DDR input registers (the building block for the LVDS_RX MegaFunction) are implemented in LE registers.

P.S.: I reviewed the implementation of LVDS_RX in Cyclone III resource property editor and it looks like if it is using input registers. Then it's clear why the clock inputs can't be regularly used as LVDS RX input.