old_contents: import mraa as m
  
  
  class SpiSerial():
      def __init__(self):
          self.cs0 = m.Gpio(23)
          self.cs0.dir(m.DIR_OUT)
          self.cs0.write(1)
  
          self.dev = m.spiFromDesc("spi-raw-5-1")
          self.dev.frequency(62500)
          self.dev.mode(m.SPI_MODE0)
          self.dev.bitPerWord(8)
          self.timeout = 0
          self.rx_buf = []
  
      def spi_xfer(self, b):
          tx = bytearray(1)
          tx[0] = (int('{:08b}'.format(b)[::-1], 2))
          self.cs0.write(0)
          rxbuf = self.dev.write(tx)
          self.cs0.write(1)
          return (int('{:08b}'.format(rxbuf[0])[::-1], 2))
  
      def close(self):
          pass
  
      def write(self, tx_bytes):
          tx_bytes = bytearray(tx_bytes)
          self.spi_xfer(0x99)
          num_rxd = self.spi_xfer(len(tx_bytes))
          for y in range(0, len(tx_bytes)):
              rx = self.spi_xfer(tx_bytes[y])
              if num_rxd > 0:
                  self.rx_buf.append(rx)
                  num_rxd -= 1
          for y in range(0, num_rxd):
              rx = self.spi_xfer(0)
              self.rx_buf.append(rx)
  
      def read(self, num_bytes=0):
          if num_bytes == 0:
              num_bytes = len(self.rx_buf)
          ret_val = self.rx_buf[0:num_bytes]
          del(self.rx_buf[0:num_bytes])
          return ret_val
  
      def inWaiting(self):
          self.spi_xfer(0x99)
          num_rxd = self.spi_xfer(0)
          for y in range(0, num_rxd):
              rx = self.spi_xfer(0)
              self.rx_buf.append(rx)
          return len(self.rx_buf)
  
  	def reset(self):
  		self.RST = m.Gpio(36)
          self.RST.dir(m.DIR_OUT)
          self.RST.write(1)	
new_contents: import mraa as m
  
  
  class SpiSerial():
      def __init__(self):
          self.cs0 = m.Gpio(23)
          self.cs0.dir(m.DIR_OUT)
          self.cs0.write(1)
  
          self.dev = m.spiFromDesc("spi-raw-5-1")
          self.dev.frequency(62500)
          self.dev.mode(m.SPI_MODE0)
          self.dev.bitPerWord(8)
          self.timeout = 0
          self.rx_buf = []
  
      def spi_xfer(self, b):
          tx = bytearray(1)
          tx[0] = (int('{:08b}'.format(b)[::-1], 2))
          self.cs0.write(0)
          rxbuf = self.dev.write(tx)
          self.cs0.write(1)
          return (int('{:08b}'.format(rxbuf[0])[::-1], 2))
  
      def close(self):
          pass
  
      def write(self, tx_bytes):
          tx_bytes = bytearray(tx_bytes)
          self.spi_xfer(0x99)
          num_rxd = self.spi_xfer(len(tx_bytes))
          for y in range(0, len(tx_bytes)):
              rx = self.spi_xfer(tx_bytes[y])
              if num_rxd > 0:
                  self.rx_buf.append(rx)
                  num_rxd -= 1
          for y in range(0, num_rxd):
              rx = self.spi_xfer(0)
              self.rx_buf.append(rx)
  
      def read(self, num_bytes=0):
          if num_bytes == 0:
              num_bytes = len(self.rx_buf)
          ret_val = self.rx_buf[0:num_bytes]
          del(self.rx_buf[0:num_bytes])
          return ret_val
  
      def inWaiting(self):
          self.spi_xfer(0x99)
          num_rxd = self.spi_xfer(0)
          for y in range(0, num_rxd):
              rx = self.spi_xfer(0)
              self.rx_buf.append(rx)
          return len(self.rx_buf)
  
      def reset(self):
          self.RST = m.Gpio(36)
          self.RST.dir(m.DIR_OUT)
          self.RST.write(1)
  
subject: fix tabs