We are running a survey to help us improve the experience for all of our members. If you see the survey appear, please take the time to tell us about your experience if you can.
I'm using Keil Debugger SW adapter and wanting to run this at 10MHz clock rate. I set the Max Clock in the target debug setup to 10MHz, but when I run the debug session and monitor the SWCLK frequency on the scope it is not 10 MHz but around 1.4MHz and the clock signal is not 50% duty cycle. Can anyone tell me why it is not 10MHz? Thanks.
The setting specifies the maximum frequency in order to limit it for slower targets. The actual signal frequency can be lower and depends on the type of packets. Also the duty cycle doesn’t’ need to be 50%.
Is there any test packet to check the max frequency of SW. I'd like to confirm if the target could response with a 10MHz clock rate.
Not really.
Is there any reference documentation that explain the frequency dependance to the type of packets?
Wouldn't such things be highly implementation dependent? What chip are you using? Are you an ARM technology licensee? Have you experimented with JLink-Ultra, or ULink-Pro type pods?
www.pjrc.com/.../ARM_debug.pdf www.arm.com/.../Serial_Wire_Debug.pdf