RTOS/IWR1642: How can I trigger sensor to start with a external HW pulse? With a programmable delay, which may range 0 ~ 10ms?

Hi,

Q1: no, hardware trigger is not support in mmwave sdk
Q2: Can you be more specific of your application? WHat do you mean by input monitoring?
Q3: No API will be sent untill sensorStart is issued, so there's no time limit between the settings and sensorStart command.
Q4: task_sleep minimum is 1msec, can't be used for 50us.

Thanks and Regards,
Michelle

Hi, Michelle,

Thanks for your reply.

for Q2: I want to implement a sensor start trigger (an external hardware pulse), and a programmable delay(0~10ms, in precision about 50us) to start sensor after pulse pos edge input. Since SYNC_IN can not support such long programmable delay, I am considering another solution for this.
1) use a GPIO in MSS, and external hardware pulse is connected to this PIN
2) create a task to monitor this GPIO, using a timer with 50us to poll this PIN state, which may create a trigger with a precision about 50us.
3) when polling precess get the pos edge of external pulse, it will trigger the rlSensorStart() function (other parameter like profile chirp, frame is already set and ready for the trigger)

Does it make sense?

I'm trying to fit our available solution to your application. One is TIDEP-0091(http:/www.ti.com/tool/TIDEP-0091). It use MSP432 to control IWR1443 through GPIO. Would this be something solve your problem?

Let me know.
Thanks and Regards,
Michelle

hi, Michelle,

Thanks for your information.

I look briefly into this demo code, and this demo seems providing method how to read and write a GPIO.

And another key part of my requiment is how to poll a pin state with a period of 50us. It seems not an easy task since HW timer is not available, and this lead me to another question: Why in swru522a chapter 15, there is a RTI (real time interupt ) while in SDK, there is no time driver?

Just to clarify:

You want the sensor start trigger and programmable delay generated inside of mmwave sensor RTI?
I initially thought the trigger is external to mmwave sensor...

Please let me know.

Thanks
Regards,
Michelle

Yes, trigger is from the external part, but the delay is programmable and updated frequently within the sensor MCU.