import spidev
import RPi.GPIO as GPIO
import time
import math

# Define GPIO pins
SYNC_PIN = 7
RESET_PIN = 22
POWER_PIN = 13

# Define SPI settings
spi = spidev.SpiDev()
spi.open(0, 1)  # SPI bus 0, device 1
spi.mode = 0b10
spi.max_speed_hz = 40000000  # 1 MHz

def setup():
    GPIO.setmode(GPIO.BCM)
    GPIO.setup(SYNC_PIN, GPIO.OUT)
    GPIO.setup(RESET_PIN, GPIO.OUT)
    GPIO.setup(POWER_PIN, GPIO.OUT)

def power_up():
    GPIO.output(POWER_PIN, GPIO.HIGH)

def power_down():
    GPIO.output(POWER_PIN, GPIO.LOW)

def reset():
    GPIO.output(RESET_PIN, GPIO.LOW)
    time.sleep(0.00004)  # Minimum of 40 ns
    GPIO.output(RESET_PIN, GPIO.HIGH)

def write_and_update_dac_channel(channel, data):
    # Construct the 24-bit command word for writing to and updating DAC channel
    command_word = (0b0011 << 20) | (channel << 16) | data

    # Send the command word over SPI
    GPIO.output(SYNC_PIN, GPIO.LOW)
    spi.xfer2([command_word >> 16, (command_word >> 8) & 0xFF, command_word & 0xFF])
    GPIO.output(SYNC_PIN, GPIO.HIGH)

def generate_sine_wave(min_value, max_value, frequency, phase_shift):
    num_samples = 10000  # 50 seconds duration
    for i in range(360):
        # Calculate the sine wave value between 0 and 1
        sine_value = (math.sin(2 * math.pi * i))

        # Scale the sine value to the range between min_value and max_value
        scaled_value = sine_value * (max_value - min_value)

        # Shift the scaled value to the range between min_value and max_value
        shifted_value = scaled_value + min_value

        # Convert the sine value to 16-bit DAC input code
        input_code = int(shifted_value)

        # Write to and update DAC Channel A with the input code
        write_and_update_dac_channel(0b0001, input_code)
        time.sleep(0.001)

def main():
    setup()
    power_up()
    reset()  # Reset the DAC initially

    try:
        while True:
            generate_sine_wave(min_value=32768, max_value=65535, frequency=1230, phase_shift=0)
    except KeyboardInterrupt:
        power_down()
        GPIO.cleanup()

if __name__ == "__main__":
    main()