Simple LED brightness control (via PCA9956)l by music envelope

envled.py

from machine import Pin, ADC, Timer
import	utime

from	machine		import	I2C
from	nxp_periph	import	PCA9956B, LED

class periodic_adc:
	def __init__( self, pin_name, *, interval = 1, scaling = (2 ** 16) ):
		self.timer_flag	= False
		self.adc		= ADC( Pin( pin_name ) )
		self.scaling	= scaling

		self.tim	= Timer(0)
		self.tim.init( period = interval, mode = Timer.PERIODIC, callback = self.timer_callback )

	def read( self, blocking = True ):
		if blocking:
			while not self.timer_flag:
				pass

		self.timer_flag	= False
				
		return self.adc.read_u16() / self.scaling

	def timer_callback( self, _ ):
		self.timer_flag	= True

def main():
	i2c		= I2C( 0, freq = (400 * 1000) )
	led_c	= PCA9956B( i2c, 0x02 >>1, iref = 0xFF )
	led_d	= PCA9956B( i2c, 0x04 >>1, iref = 0xFF )
	leds	= [ LED( led_c, i ) for i in range( led_c.CHANNELS ) ]

	adc	= periodic_adc( "A0", interval = 10 )
	
	for i in range( 3 ):
		leds[ 0 ].v	= 1.0
		utime.sleep( 0.1 )
		leds[ 0 ].v	= 0.0
		utime.sleep( 0.1 )

	count	= 0
	
	while True:
		v	= adc.read()
#		leds[ count % led_c.CHANNELS ].v	= v * v
		led_c.pwm( [ v ] * led_c.CHANNELS )
		led_d.pwm( [ v ] * led_d.CHANNELS )
		count	+= 1
		
if __name__ == "__main__":
	main()