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

# Setup GPIO
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):
    # Convert data to an integer
    data = int(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():
    SINE_DC_OFFSET = 32768
    SINE_AMPLITUDE = 32767

    SINE_WAVE_STEPS = 100
    STEP_DELAY_MICROS = 8.13

    sineWave = [0] * SINE_WAVE_STEPS

    for i in range(SINE_WAVE_STEPS):
        sineWave[i] = SINE_DC_OFFSET + SINE_AMPLITUDE * math.sin(i * 2 * math.pi / SINE_WAVE_STEPS)

    i = 0
    while True:
        write_and_update_dac_channel(0b0001, sineWave[i])
        i = (i + 1) % SINE_WAVE_STEPS
        #time.sleep(STEP_DELAY_MICROS / 1000000)  # Convert to seconds

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

    try:
        generate_sine_wave()
    except KeyboardInterrupt:
        power_down()
        GPIO.cleanup()

if __name__ == "__main__":
    main()