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NIOS Reset Button Not working in Max10 Kit

Honored Contributor II

I am working with max 10 fpga development kit (https://cloud.altera.com/devstore/board/max-10-fpga-development-kit/) and demo of Nios II Simple Socket Server Ethernet Example. 

SSS works well after changing few things ( Flash address definition ). 


But I could not reset NIOS by pressing CPU_RESETn on KIT. 


Another question: 

in the "m10_rgmii.v", why they use user_pb[0] ? 



BTW: When I use simple QSYS demo (without ETH, DDR), reset button works fine.  

So I guess there might be a reset circuit issue within "m10_rgmii.v". 





//PHY power-on reset control 

parameter MSB = 20; // PHY interface: need minimum 10ms delay for POR 

reg [MSB:0] epcount; 



always @(posedge clk_50_max10 or negedge fpga_resetn) 

if (!fpga_resetn) 

epcount <= MSB + 1'b0; 

else if (epcount[MSB] == 1'b0) 

epcount <= epcount + 1; 


epcount <= epcount; 



assign phy_resetn = user_pb[0] & !epcount[MSB-1]; 

assign enet_resetn = phy_resetn;
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