kooka — access to Kookaberry specific peripherals

This module provides access to the Kookaberry specific peripherals like the display, buttons and accelerometer. Objects for these internal peripherals are created at start-up and available via the instance names given below.

Instances

kooka.led_red
kooka.led_orange
kooka.led_green

These objects give access to the three LEDs on the board. They are instances of class LED.

kooka.button_a
kooka.button_b
kooka.button_c
kooka.button_d

These objects give access to the four buttons on the board. They are instances of class Button.

kooka.display

This gives acces to the display on the board, an instance of class SH1106_SPI.

kooka.accel

This is the on-board accelerometer, an instance of class LSM303C_Accel.

kooka.compass

This is the on-board magnetometer, an instance of class LSM303C_Mag.

kooka.radio

This handles the interface to the 2.4GHz radio (nRF51822), an instance of class Radio.

Functions

kooka.neopixel_write(pin, timing_ns, buf)

Write the bytes in buf to a NeoPixel-like device on the given pin. Any pin can be used and interrupts will be disabled during the entire write to get accurate timing. The timing_ns argument should be a 4-tuple of integers which specify the 0-high, 0-low, 1-high, 1-low timing values in nanoseconds to use when generating the output bit stream. Typical timing values are (450, 800, 850, 400) and should be tuned for the specific LED hardware. The bytes from buf are output big endian.

class LED

This class allows you to turn the built-in LEDs on and off.

Methods

kooka.on()

Turn the LED on.

kooka.off()

Turn the LED off.

kooka.toggle()

Toggle the LED between on and off.

class Button

This class allows you to read the state of one of the built-in buttons and includes automatic debouncing.

Methods

kooka.value()

Return the current state of the debounced button: 0 for released and 1 for pressed (debouncing has been performed on the return value).

Pin.__call__()

Button objects are callable, providing a fast shortcut to get the value of the button. It is equivalent to Button.value().

kooka.is_pressed()

Returns True if the debounced button is held down, False otherwise.

This method is mainly provided for compatibility with the micro:bit.

kooka.was_pressed()

This method gives access to the history of the button, allowing you to test if the button was pressed down since the last call to this method. It returns True if it was pressed down, False otherwise.

In detail: when the debouncing algorithm (which runs in the background) determines that the button went from being not held to held, the button remembers that it was pressed. It will remember this until was_pressed() is called at which point it will return True and clear this state. It will then return False if called again, until the button is pressed down again.

class Servo – 3-wire hobby servo driver

This class allows you to control standard hobby servo motors with 3-wires (ground, power, signal). There are 4 available servo ports on P2, P3, P4 and P5.

Example usage:

from kooka import Servo

s1 = Servo('P2')   # create a servo object on connector P2
s2 = Servo('P5')   # create a servo object on connector P5

s1.angle(45)        # move servo 1 to 45 degrees
s2.angle(0)         # move servo 2 to 0 degrees

# move servo1 and servo2 synchronously, taking 1500ms
s1.angle(-60, 1500)
s2.angle(30, 1500)

Constructors

class kooka.Servo(id)

Create a servo object. The parameter id can be a string naming the connector, like "P2", or a class Pin – control I/O pins object representing the pin on the connector.

Methods

Servo.freq([freq])

If no arguments are given, this function returns the current servo PWM frequency in Hz.

If an argument is given then it sets the servo PWM frequency in Hz.

Servo.angle([angle, time=0])

If no arguments are given, this function returns the current angle of the servo.

If arguments are given, this function sets the angle of the servo:

  • angle is the angle to move to in degrees.

  • time is the number of milliseconds to take to get to the specified angle. If omitted, then the servo moves as quickly as possible to its new position.

Servo.speed([speed, time=0])

If no arguments are given, this function returns the current speed.

If arguments are given, this function sets the speed of the servo:

  • speed is the speed to change to, between -100 and 100.

  • time is the number of milliseconds to take to get to the specified speed. If omitted, then the servo accelerates as quickly as possible.

Servo.pulse_width([value])

If no arguments are given, this function returns the current raw pulse-width value in microseconds.

If an argument is given, this function sets the raw pulse-width value in microseconds.

Servo.calibration([pulse_min, pulse_max, pulse_centre[, pulse_angle_90, pulse_speed_100]])

If no arguments are given, this function returns the current calibration data, as a 5-tuple.

If arguments are given, this function sets the timing calibration:

  • pulse_min is the minimum allowed pulse width.

  • pulse_max is the maximum allowed pulse width.

  • pulse_centre is the pulse width corresponding to the centre/zero position.

  • pulse_angle_90 is the pulse width corresponding to 90 degrees.

  • pulse_speed_100 is the pulse width corresponding to a speed of 100.