This example (ISXMPL3750ex3) demonstrates how to use the IS3750 Addressable LED Controller chip with an Arduino microcontroller board using the Arduino functions.
You can find the complete example at:
You can get the IS3750 evaluation board (Kappa3750Ard) compatible with Arduino UNO form factor boards at:
from smbus2 import SMBus, i2c_msg
import time
I2C_BUS = 1 # Use 1 for most Raspberry Pi models
DEVICE_ADDRESS = 0x12 # 7-bit I2C address of the IS3750
# IS3750 register map
REGISTER_SHOW = 0x00
REGISTER_LED1_RED = 0x01
REGISTER_LED1_GREEN = 0x02
REGISTER_LED1_BLUE = 0x03
REGISTER_LED2_RED = 0x04
REGISTER_LED2_GREEN = 0x05
REGISTER_LED2_BLUE = 0x06
REGISTER_LED3_RED = 0x07
REGISTER_LED3_GREEN = 0x08
REGISTER_LED3_BLUE = 0x09
def write_register(start_register, data_bytes):
"""
Write a block of data starting at a 16-bit register address.
:param start_register: The 16-bit register address to start writing to.
:param data_bytes: A list of bytes to write.
"""
high_addr = (start_register >> 8) & 0xFF
low_addr = start_register & 0xFF
with SMBus(I2C_BUS) as bus:
msg = i2c_msg.write(DEVICE_ADDRESS, [high_addr, low_addr] + data_bytes)
bus.i2c_rdwr(msg)
def show_leds():
"""Send the 'show' command to apply the LED updates."""
write_register(REGISTER_SHOW, [1])
def clear_all_led_registers():
"""Clear all LED registers by sending 3600 zero bytes."""
data = [0] * (1200 * 3)
write_register(REGISTER_LED1_RED, data)
# Example usage loop
while True:
clear_all_led_registers()
write_register(REGISTER_LED1_GREEN, [5])
show_leds()
time.sleep(1)
clear_all_led_registers()
write_register(REGISTER_LED2_RED, [5])
write_register(REGISTER_LED2_GREEN, [5])
show_leds()
time.sleep(1)
clear_all_led_registers()
write_register(REGISTER_LED3_RED, [5])
show_leds()
time.sleep(1)
