To use the CRICKIT with MicroPython, you will need the Adafruit seesaw.py driver code loaded onto the board in addition to your user program named main.py.
The seesaw driver code is below. You can use the Download function to put it on your computer. The best location to download seesaw.py depends on your operating system.
Place the file seesaw.py into your mu_code folder, which might be in:
- C:\Users\YourUserName\mu_code on Windows
- /Users/YourUserName/mu_code on macOS
Putting it in the mu_code folder makes it much easier to copy the files onto the micro:bit on the next page.
# SPDX-FileCopyrightText: 2019 Limor Fried for Adafruit Industries
#
# SPDX-License-Identifier: MIT
# Adafruit Seesaw / CRICKIT driver for MicroPython
# MIT License by Adafruit Industries Limor Fried
# Copy onto the micro:bit with main.py using Mu Files icon
from microbit import i2c
import struct
import time
_SIGNALS = (2, 3, 40, 41, 11, 10, 9, 8)
_PWMS = (14, 15, 16, 17, 19, 18, 22, 23, 42, 43, 12, 13)
_SERVOS = (17, 16, 15, 14)
_MOTORS = (22, 23, 19, 18)
_DRIVES = (13, 12, 43, 42)
_TOUCHES = (0, 1, 2, 3)
_ADDR = 0x49
reg_buf = bytearray(2)
pwm_buf = bytearray(3)
def _read(reghi, reglo, n, delay_s=0.01):
reg_buf[0] = reghi
reg_buf[1] = reglo
i2c.write(_ADDR, reg_buf)
time.sleep(delay_s)
return i2c.read(_ADDR, n)
def _write(reghi, reglo, cmd):
reg_buf[0] = reghi
reg_buf[1] = reglo
#print("sswrite: ", [hex(i) for i in reg_buf+cmd])
i2c.write(_ADDR, reg_buf+cmd)
# t is between 1 and 4
def read_touch(t):
return struct.unpack(">H", _read(0x0F, 0x10+_TOUCHES[t-1], 2))[0]
def pwm_write(pwm, val):
pwm_buf[0] = _PWMS.index(pwm)
pwm_buf[1] = val >> 8
pwm_buf[2] = val & 0xFF
_write(0x08, 0x01, pwm_buf)
def set_pwmfreq(pwm, freq):
pwm_buf[0] = _PWMS.index(pwm)
pwm_buf[1] = freq >> 8
pwm_buf[2] = freq & 0xFF
_write(0x08, 0x02, pwm_buf)
# signal is between 1 and 8
def analog_read(signal):
return struct.unpack(">H", _read(0x09, 0x07+signal-1, 2))[0]
def pin_config(pin, mode, pull=None, val=None):
if pin >= 32:
cmd = struct.pack(">I", 1 << (pin - 32))
cmd = bytearray(4) + cmd
else:
cmd = struct.pack(">I", 1 << pin)
if 0 <= mode <= 1:
_write(0x01, 0x03-mode, cmd)
if pull is not None and 0 <= pull <= 1:
_write(0x01, 0x0C-pull, cmd)
if val is not None and 0 <= val <= 1:
_write(0x01, 0x06-val, cmd)
def init():
i2c.init()
while not _ADDR in i2c.scan():
print("Crickit not found!")
time.sleep(1)
reg_buf[0] = 0x7F
reg_buf[1] = 0xFF
i2c.write(_ADDR, reg_buf)
# s is between 1 and 4
def servo(s, degree, min=1.0, max=2.0):
set_pwmfreq(_SERVOS[s-1], 50)
val = 3276*min + (max-min)*3276*degree/180
pwm_write(_SERVOS[s-1], int(val))
# d is between 1 and 4
def drive(d, frac, freq=1000):
set_pwmfreq(_DRIVES[d-1], freq)
pwm_write(_DRIVES[d-1], int(frac*65535))
# m is 1 or 2
def motor(m, frac, freq=1000):
m -= 1 # start with 1
pin1,pin2 = _MOTORS[m*2:m*2+2]
set_pwmfreq(pin1, freq)
set_pwmfreq(pin2, freq)
if frac < 0:
pin1, pin2 = pin2, pin1
pwm_write(pin1, 0)
pwm_write(pin2, abs(int(frac*65535)))
# signal is between 1 and 8, val is 0 or 1
def write_digital(signal, val):
pin_config(_SIGNALS[signal-1], 1, 0, val) # output, pullup, value
# signal is between 1 and 8
def read_digital(signal):
pin = _SIGNALS[signal-1]
pin_config(pin, 0, 1, 1) # input, pullup, pullvalue
ret = _read(0x01, 0x04, 8)
b = 0
if pin > 32:
b = 4
pin -= 32
b += 3 - (pin // 8)
return (ret[b] & 1<<(pin % 8)) != 0
Page last edited January 22, 2025
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