cp.pixels

a list of 10 pixels on the Circuit Playground Express

DESCRIPTION

You can use this list to set the color of the 10 pixels on your board. The color value of a pixel is represented by three numbers ranging from 0-255 for red, green, and blue in that order.

set pixel 1 to red

• cp.pixels[0] = (255, 0, 0)

If you set the color of a pixel using the method shown above, the pixel will be set the that color, but it will not turn on. To turn on the pixels, you need to use the pixels.show() method.

set pixel 1 to red and turn it on

• cp.pixels[0] = (255, 0, 0)

• cp.pixels.show()

cp.play_tone(hertz, seconds)

plays a tone for a duration

DESCRIPTION

Plays a tone at a given hertz level for a given number of seconds. Human hearing range is from 40 - 20,000 hertz. Lower numbers are lower sound (bass) and higher numbers are high sounds (treble).

play 800 hz tone for 2 seconds

• cp.play_tone(800, 2)

cp.button_a / cp.button_b

get input from the two buttons

DESCRIPTION

Returns True or False if the button is pressed.

Check if button A is pressed

• if cp.button_a:

cp.switch

get input from the switch

DESCRIPTION

Returns True or False if the slide switch is in the left or right position.

Check switch

• if cp.switch:

cp.temperature

get the ambient temperature of the room

DESCRIPTION

Returns a number representing the temperature of the room in celsius. To convert to fahrenheit, multiply it by 1.8 and then add 32.

Check if temperature is above 90F

if cp.temperature * 1.8 + 32 > 90:

cp.acceleration

get the rotation of the board in either the x, y, or z rotations

DESCRIPTION

When the board is held still in any given position, it is still being affected by gravity. Gravity is -9.8m/s2. So, at any given point in time, that value is being applied downward. For example, the values returned if the board is laying flat, facing up, are (0, 0, 9.8), because gravity is pulling on the sensor along the z axis. If you were to pick up the board and shake it, you'll find that you get much higher values. This is because the force with which you are shaking the board causes increased acceleration to be applied to the sensor along whichever axes you are shaking it.

Check if board is upside down

if cp.acceleration.z < 0:

cp.light

get the ambient light level of the room

DESCRIPTION

Returns the ambient light level of a room as a number from 0-320 with 320 being the brightest. A well-lit room is about 30.

Check if the lights are on

if cp.light > 30:

random.randrange(start, stop)

get a random number

DESCRIPTION

Returns a random number from a given range. Start value is inclusive and the stop value is exclusive.

Turn on the first pixel to a random color every two seconds

random.randrange(0, 255)