[question] V5 Motor Update Frequency

VEX V5 Technical Support OFFICIAL Tech Support
1

Technical question about the V5 Smart Motor’s update frequency.

Consider the following:

motor.move(125);
pros::delay(5);
motor.move(126);
pros::delay(5);
motor.move(127);

at the end of the sequence, would the motor power level be 126 or 127? (assume the thread is aligned with vexBackgroundProcessing

2

Unless it changed since I last checked, V5 motors are updated at 200Hz.
That alone can’t answer your question though, because the brain is not commanding the motor directly.
It’s the motor that controls the timing. At 200Hz, it queries the brain every 5ms (of Motor-local time) for the last command.
Your motor commands in fact only prepare a message for the motor in its mailbox. If you, for example, keep changing the command in a tight loop, that single message will get updated in the mailbox till the brain picks it up.

With your scenario, you can happily assume the motor will get commanded to 127 by the end of the sequence or shortly after, depending on the phase lag between that particular motor and your 5ms delay sequence. Other motors connected to your brain (say within a motor group) could and would have a different phase lag.

Also note that your 5ms delay is very likely not “wait 5ms”, but rather “wait for the 5th edge of the millisecond counter”, which could be anything from 4-6ms (either 4-5ms or 5-6ms, depending on the bias of the implementation)

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