When the clock is given directly to the output pin, you should be seeing the exact clock frequency you have set as output. In case you have set tolerance in the clock block, you should see the output in the range as shown below:
For 7Mhz the output might range will be between 6.65MHz - 7.35MHz. If you unchecked the tolerance, you should see a more accurate 7MHz.
From the looks of it, seems like you might have changed some settings in the clocks or the divider values. So, it would be great if you could share your project here so that I can have a look. Also, let me know what frequency you are observing, a screenshot of the oscilloscope output would be great.
Looking forward to your reply.
Dheeraj D Kamath
What does it mean ''not perfect' - frequency is off?
The clock divider is an integer number, so to get 7MHz, the Master clock must be any of 77MHz, 70MHz, 63MHz, 56MHz, 49MHz, ... In the clocks section set PLL to one of those values.
i was trying everything in a clock.
whenever i was put the 7 mhz clock on to the output pin i was just give it the 6MHz or 8MHz frequency but i was never take it the 7mhz frequency .
i was also tryed to the timer and pwm but same problem is occur .
actually i want to generate the different different frequency on a single output pin.
below i was attached the output of the CRO to the 7mhz clock.@Problem to generate Clock Frequncy ?
It is not possible to get finely tunable frequency around 7 MHz using standard Timer or PWM, due to high granularity of the divider. For example, with MASTER_CLK=70 MHz, and dividers 9, 10 or 11 the output frequency will be accordingly: 7.777 MHz, 7.0 MHz or 6.363 MHz.
One way to get fine-tuned output is to utilize DDS approach. You can try using either DDS24 or DDS32 components for that:
Thanks Guys for Helping me
it means a lot.
now i am generated the 7 mhz frequency but this shape is not good .
i am wanted the square wave 7mhz output.
thank you so much for helping me.
ok. i will try this.
and by the way thanks.
The output is usually a square wave. Check the schematic of the board you are using whether there is a cap on the pin for buffering. Looks a bit as if so. Which Board are you using and which port your output is sent to? How is the pin configured??
Can you please post your complete project or a shortened version that shows the error so that we all can have a look at all of your settings. To do so, use
Creator->File->Create Workspace Bundle (minimal)
and attach the resulting file.
It could also be a oscilloscope probe issue. Use the probe in 10x mode. You can also try adjusting the probe compensation.
HELLO i am configuring the output pin as a pull up and and this pin is directly connected to clock this clock is 49mhz master clock and divider by 7 i am taking the 7 mhz output but not the sharp value or graph is not an squre wave.
i was also try this nothing change will be happen.
You need to set the pin drive mode to "strong".
i was already done this.nothing change it will happen.and i am using lp05 kit.