shape of the Ramp is getting distorted for Higher frequency

Submitted by shiva_shankar on Mon, 02/25/2013 - 07:17

Hello All,

I am using the Variable frequency ramp generator. For lower frequency shape of the ramp signal is smooth. As i increase the frequency the shape of the Ramp is distorted.

I am using TMS320F20862 controller and Spectrum digital emulator, when debug the shape of the ramp signal is distorted. system properties > step time is set to 0.0005 seconds. Is there any solution such that my ramp signal should not get distorted for higher frequency. Here i have attached the .vissim file.

Please suggest us a solution.

Thank you shivashankar

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You seem to be missing a few

Submitted by Anders89 on Mon, 02/25/2013 - 13:30.

The ramp shape is fine. You seem to be missing a few key concepts. We think you are clicking the go button and not first compiling your diagram.

  1. The JTAG speed is only 100-500Hz.
  2. If you check the "Enable Interactive Peripheral Mode", only peripheral blocks like ADC and PWM run on the target. All other blocks run on the PC.
  3. To run your code with out jitter, capture high speed wave forms on the target and plot them in digital scopes on the PC, you must compile your code and use the monitor buffers and the targetInterface block as described here.

See attached diagram.