import machine
import utime

# Define GPIO pins for TMC2209
STEP_PIN = 22
DIR_PIN = 23
UART_TX_PIN = 18
UART_RX_PIN = 19

# Define pins for TMC2209 driver
step_pin = machine.Pin(STEP_PIN, machine.Pin.OUT)
dir_pin = machine.Pin(DIR_PIN, machine.Pin.OUT)

# Define UART parameters
uart = machine.UART(1, baudrate=115200, tx=UART_TX_PIN, rx=UART_RX_PIN)

# Set initial pin states
step_pin.value(0)
dir_pin.value(0)

# Define stepper motor parameters
steps_per_rev = 400   # Number of steps per revolution
microsteps = 1        # Microstepping mode (1, 2, 4, 8, 16)
rpm = 1               # Desired revolutions per minute
delay = 60 / (steps_per_rev * microsteps * rpm)   # Delay between steps

# Set current level (A) to 1.68A
uart.write(b'\x01\x00\x0F\xA0')  # Send IHOLD_IRUN register write command via UART

# Set stealthChop mode
uart.write(b'\x05\x00\x00\x03')  # Send GCONF register write command via UART
uart.write(b'\x01\x00\x01\x10')  # Send IHOLD_IRUN register write command via UART
uart.write(b'\x05\x00\x00\x01')  # Send GCONF register write command via UART

# Define step direction function

def step():
    step_pin.value(1)
    utime.sleep_us(1)
    step_pin.value(0)
    utime.sleep_us(1)

# Main loop
while True:
    dir_pin.value(0)
    for i in range(steps_per_rev * microsteps):
        step()   # Step in one direction
        utime.sleep_us(int(delay))
    dir_pin.value(1)
    for i in range(steps_per_rev * microsteps):
        step()   # Step in the opposite direction
        utime.sleep_us(int(delay))