Serial Flash Controller IP Clock Speed

[James_B]

I would like to confirm that the serial flash controller IP is only recommended to run at 25 MHz clock, as per the application note AN-736 on the website updated on 2016.05.20.

My Nios currently runs at 50 MHz, looking at how to handle this.

Thanks.

[Fawaz_Al-Jubori]

Hello sir, The Serial Flash controller speed might be start from 20MHz up to 25MHz max. You can add a PLL IP to your system, the input clock of this PLL will be your clock source on board. Then, you can extract two clocks from PLL, one for the system (Nios II , and other IPs) with a value up to 100MHz (you can achieve higher speed, yet it would be hard to close timing). And the other clock is 25MHz to Serial Flash Controller IP. Thanks

[James_B]

FJumaah, Thanks for the feedback.

[Fawaz_Al-Jubori]

You are welcome sir, Kindly select as best answer if you are satisfied with my reply. Let me know also if you need further assistance. Thanks

[James_B]

FJumaah, Thank you for your answer. Yes, it is helpful. I will plan to use 2 clocks, one for Nios and one for the serial flash. I trust that there will be no clock domain crossing issues here.... Thanks, James

[Fawaz_Al-Jubori]

You are welcome.

[HAlex]

Hello 

Just wanted to know if there are no clock domains issues when connecting Nios running at 100Mhz and Flash controller IP running in a slower speed?

I want to use Remote update and to program serial flash with an application image from Nios.

Flash controller IP currently connected exactly as shown on figure 3 above (to instruction and data master buses of Avalon).

Or I need to connect Nios and Flash controller IP through a bridge?

I am using EP4CGX150CF23C8N.

Thank you

Alex