Elevator stepper motor python

ascensor.py

import time
import smbus

#bus = smbus.SMBus(0)  # Rev 1 Pi uses 0
bus = smbus.SMBus(1) # Rev 2 Pi uses 1

DEVICE = 0x20 # Device address (A0-A2)
IODIRA = 0x00 # Pin direction register
IODIRB = 0x01 # Pin direction register
OLATA  = 0x14 # Register for outputs
OLATB  = 0x15 # Register for outputs
GPIOA  = 0x12 # Register for inputs
GPIOB  = 0x13 # Register for inputs

# Set all GPA pins as outputs by setting
# all bits of IODIRA register to 0
bus.write_byte_data(DEVICE,IODIRA,0x00)
bus.write_byte_data(DEVICE,IODIRB,0xFF)
lectura = bus.read_byte_data(DEVICE,IODIRB)
print(lectura)


class Ascensor:
    def __init__(self, piso_actual = 0, piso_destino = 1, altura_piso = 400, direccion = "sube"):
        self.piso_actual = piso_actual
        self.piso_destino = piso_destino
        self.altura_piso = altura_piso
        self.direccion = direccion
        self.pasos = (self.piso_destino - self.piso_actual) * self.altura_piso
        self.halfstep_seq_cw = [
                0b00001000, # 1,0,0,0
                0b00011000, # 1,1,0,0
                0b00010000, # 0,1,0,0
                0b00110000, # 0,1,1,0 
                0b00100000, # 0,0,1,0
                0b01100000, # 0,0,1,1
                0b01000000, # 0,0,0,1
                0b01001000 # 1,0,0,1
        ]
        self.halfstep_seq_ccw = [
                0b01001000, # 1,0,0,1
                0b01000000, # 0,0,0,1
                0b01100000, # 0,0,1,1
                0b00100000, # 0,0,1,0
                0b00110000, # 0,1,1,0
                0b00010000, # 0,1,0,0
                0b00011000, # 1,1,0,0
                0b00001000 # 1,0,0,0
            ]

    def vamos(self, piso_destino):
        self.piso_destino = piso_destino
        self.pasos = (self.piso_destino - self.piso_actual) * self.altura_piso
        print(self.pasos)
        if self.pasos < 0:
            self.direccion = "baja"
            self.pasos = self.pasos * -1
        elif self.pasos > 0:
            self.direccion = "sube"
        else:
            self.direccion = "para"

        for i in range(self.pasos):
            for halfstep in range(8):
                if self.direccion == "sube":
                    bus.write_byte_data(DEVICE,OLATA,self.halfstep_seq_cw[halfstep])
                elif self.direccion == "baja":
                    bus.write_byte_data(DEVICE,OLATA,self.halfstep_seq_ccw[halfstep])
                time.sleep(0.001)
        self.piso_actual = self.piso_destino
        print(f"Estamos en el piso {self.piso_actual}")
        bus.write_byte_data(DEVICE,OLATA,0b00000000)

asc = Ascensor()

while True:
    lectura = bus.read_byte_data(DEVICE,GPIOB)
    
    if lectura == 0b00000001:
        print(f"bot bajo! dec: {lectura} bin: {bin(lectura)}" )
        asc.vamos(0)
        time.sleep(0.5)
    elif lectura == 0b00000010:
        print(f"bot primero! dec: {lectura}  {bin(lectura)}")
        asc.vamos(1)
        time.sleep(0.5)
    elif lectura == 0b00000100:
        print(f"bot segundo! dec: {lectura}  {bin(lectura)}")
        asc.vamos(2)
        time.sleep(0.5)
    elif lectura == 0b00001000:
        print(f"bot tercero! dec: {lectura}  {bin(lectura)}")
        asc.vamos(3)
        time.sleep(0.5)
    elif lectura == 0b00010000:
        print(f"bot cuarto! dec: {lectura}  {bin(lectura)}")
        asc.vamos(4)
        time.sleep(0.5)
    elif lectura == 0b00100000:
        print(f"bot quinto! dec: {lectura}  {bin(lectura)}")
        asc.vamos(5)
        time.sleep(0.5)
    time.sleep(0.01)