4.1.1. LED Control¶
Your OpenMV Cam has an RGB LED and two IR LEDs on board. You can control the
red, green, and blue segments of the RGB LED individually and the two IR LEDs as
one unit. To control the LEDs first import the
pyb module. Then create an
LED class object for the particular LED you want to control:
import pyb red_led = pyb.LED(0) green_led = pyb.LED(1) blue_led = pyb.LED(2) ir_leds = pyb.LED(3)
pyb.LED(number) call creates an LED object which you can use to control
a particular LED. Pass
pyb.LED “0” to control the red RGB LED segment, “1”
to control the green RGB LED segment, “2” to control the blue RGB LED segment,
and “3” to control the two IR LEDs.
After creating the LED control objects like above I heavily recommend that you
off() method for a new LED to put it into a known state.
Anyway, there are three methods you can call for each LED,
toggle() which do exactly that.
Unlike other MicroPython Boards the OpenMV Cam doesn’t support the
method to allow for PWM dimming of the LEDs. We re-purposed the timer that was
used for LED dimming for generating a clock source to power the camera chip.
Finally, use the RGB LED for indicator purposes in your script. As the IR LEDs, those are for night vision. When you switch out your OpenMV Cam’s regular lens for our IR lens (which is a lens without an IR filter) you can then turn on the IR LEDs so that your OpenMV Cam can see in the dark. The IR LEDs are strong enough to illuminate about 3 meters in front of your OpenMV Cam in pitch black.