Timer

Introduction

The VEX AIM Coding Robot’s timer keeps track of elapsed time from the start of a project. It can be used to measure durations, trigger events after a set time, or reset for new timing operations. Below is a list of all available methods:

Action – Control the timer.

• reset – Resets the timer to zero.

Getter – Return the current timer value.

• time – Returns the elapsed time since the project started.

Callback – Trigger functions after a delay.

• event – Calls a function after a specified number of milliseconds, with optional arguments.

Constructor - Create a Timer to track time.

• Timer - Create a new timer object that can be used with these methods.

Action

reset

reset sets the timer to zero.

Usage:

timer.reset()

Parameters	Description
	This method has no parameters.

# Display how long a turn takes
robot.move_for(100, 0)
timer.reset()
robot.turn_for(RIGHT, 90)
robot.screen.print("Time elapsed:")
robot.screen.next_row()
robot.screen.print("%d seconds" % timer.time(SECONDS))

Getter

time

time returns the current elapsed time of the timer in the specified units — an integer for MSEC or a float for SECONDS.

Usage:

timer.time(units)

Parameters	Description
units	The time units are milliseconds MSEC (default) or SECONDS.

# Print the time in seconds
# and in milliseconds on the next row.
while timer.time(SECONDS) <= 5:
    robot.screen.clear_screen()
    robot.screen.set_cursor(1, 1)
    robot.screen.print("Time: %d" % timer.time(MSEC))
    robot.screen.next_row()
    robot.screen.print("Time: %.2f" % timer.time(SECONDS))
    wait(50, MSEC)

Callback

event

event calls a function after a specified amount of time.

Usage:

timer.event(callback, delay, arg)

Parameters	Description
callback	A function to execute when the timer event occurs.
delay	The delay before the function is called, in milliseconds.
arg	Optional. A tuple containing arguments to pass to the callback function. See Using Events with Parameters for more information.

# Create a function to play a sparkle sound
def timer_callback():
    robot.sound.play(SPARKLE)

# Call the function after 2000 milliseconds (2 seconds)
timer.event(timer_callback, 2000)

Constructor

Timer

A new timer can be created using the Timer constructor. A new timer starts measuring time immediately when it is created.

Usage:
Timer()

Parameter	Description
	This constructor has no parameters.

## Display 2 timers with a 2 second difference
wait(2, SECONDS)

stopwatch = Timer()

while True:
    robot.screen.clear_screen()

    robot.screen.set_cursor(1, 1)
    robot.screen.print("Timer:")
    robot.screen.set_cursor(2, 1)
    robot.screen.print(timer.time(SECONDS))

    robot.screen.set_cursor(4, 1)
    robot.screen.print("Stopwatch:")
    robot.screen.set_cursor(5, 1)
    robot.screen.print(stopwatch.time(SECONDS))

    wait(0.1, SECONDS)