Simple Python USB OBD II RPM and Speed Reader

rpm.py

import serial
from time import sleep

#Play around with timeout to see if I can improve refresh rate
ser = serial.Serial("/dev/tty.usbserial", 38400, timeout=0.1)

for x in range(0, 100):
    ser.write("01 0C\r")
    sleep(0.05)
    rpm_hex = ser.readline().split(' ') #Try other read methods to increase speed
    rpm_int = int('0x'+rpm_hex[3]+rpm_hex[4], 0) / 4
    
    ser.write("01 0D\r")
    sleep(0.05)
    speed_hex = ser.readline().split(' ') #Try other read methods to increase speed
    speed_double = int('0x'+speed_hex[3], 0)
    
    print "rpm:", rpm_int, "\rspeed:", speed_double, "\r"
    
ser.close()