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12435 Discussions

Controlling HPS pins from FPGA using Cyclone 5

Honored Contributor II



I am trying to blink a LED which is connected to the HPS from a button connected on the FPGA. I have built the Qsys design and Loaned the I/O desired pins to the top level entity, then by setting the loan_io_oe[x] to 1 will let the connection be as an output and could be controlled by the loan_io_out[x], however I get no response. When doing the opposite procedure it works!! by letting a button connected to HPS to control a LED connected to FPGA. 


So what could be the problem here? I have been stuck for days on it. 



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Honored Contributor II

Hi, do you update the preloader on the device? Note that the Pin Mux for the IO is located within the HPS - as such you will need to update the preloader once you set a Loan I/O to the HPS.