Microblaze clock problem with DCM and global buffer

[umer_366]

hi all

i am attaching ADC with the miceoblaze and ADC works with 30 MHz clock speed .

while my FFT core and VGA works at 50 MHz clock speed and i have attached them with the microblaze.

system clock is of 50 MHz..

can i use DCM to make a connection these 3 design with the same microblaze???

the reason what i have found is that thereis a global buffer which is used by the microblaze to make the 50 MHz clock stable....

and whenever i use DCM to convert the 50 MHz to 30 MHz then it does not result with the microblaze...

is there any limitation like that???

or there may be some other reason???

thanks
.

 

[vipinlal]

I tried something like this once with DCM and I got some error saying " cannot drive multiple drivers".
Right now you are using the system clock for driving FFT and VGA. The same clock via a DCM you are converting to 30MHz and used to drive microblaze.

Can you try something like this:
Use two DCM's: one with external clock supply and another with internal clock supply.
Use clk1 to drive FFT and VGA. Use clk2 to drive microblaze.

the code may look something like this:

clk1 : dcm1 port map ( CLKIN_IN => Clk50,
CLKDV_OUT => Clk_VGAandFFT, --let the division factor be "1".
CLKIN_IBUFG_OUT => Clk2dcm2,
CLK0_OUT => open );

clk2 : dcm2 port map ( CLKIN_IN => Clk2dcm2,
CLKDV_OUT => Clk_microblaze, --divide clock appropriatly
CLK0_OUT => open );

 

[umer_366]

thanks for replying
i want to ask that i am using microblaze to controll the flow in c...
u are saying this to do it in ise design...
may i come to know where to do that modification in my design???