SPI CLOCK FROM FPGA NOT FROM SPI MASTER

[nhzgroup]

Hello all, 

I have an artix-7 FPGA connected to MASTER SPI (FX3). First, when I try to configure FPGA I fail. I check SPI_SCK or CCLK during operation and wierd thing is there. 

When I power on the board I see FPGA send a ~2.5 MHz clock into CCLK!!!!! PICTURE BELOW:

When I start sending bitstream through SPI i see two clock added!! picture below

Any one know what is going on?

Thanks, 

[simon]

Hi @nhzgroup 

What's the frequency of these two? It looks as if there is a crosstalk.

[drjohnsmith · Accepted solution]

what configuration mode do yo have the fpga set into ?

it looks like its configured to be master, which is why its sending out the cclk.

You dont say your board or FPAG , bu there ar enormal three mode pins to the FPGA M0, M1 M2 which sleect what the FPGA does upon a prog_b going down,

https://www.xilinx.com/support/documentation/user_guides/ug470_7Series_Config.pdf

https://www.xilinx.com/support/answers/34904.html

[nhzgroup]

Thanks 

drjohnsmith, You were right! the problem solved ! got stuck with this for many days! god bless you. Best,