When I use FreeMaster, when DAP connects to the highest speed and collects variables at 200kHz, the displayed waveform always has problems, while low-frequency ones are fine. Why is this? The speed is always set to the fastest
Hello,
it is a simple question, but it is not so easy to answer. Our experiments show that with CMSIS-DAP at default 1MHz, the maximum is around 2k of 32bit samples per second. Increasing the DAP clock speed does not always bring the desired performance increase. With JLink it may reach up to 10k samples.
The fastest communication interface is a USB CDC port implemented by USB-enabled NXP devices (see fmstr_usb_cdc demo) or UDP communication for NXP devices with Ethernet interface.
Anyway, FreeMASTER was not really intended to be used as a high speed live recorder. In order to capture transitions at very high speed, use a FreeMASTER Recorder feature - which runs at the MCU side and uses on-chip memory for recording. With FreeMASTER Recorder, you should be able to record data around 100kHz rate.
Regards,
Michal