import spidev
import time
import sys

spi = spidev.SpiDev()
spi.open(0, 0)
spi.max_speed_hz = 1000000

while True:
    try:
        resp = spi.xfer2([0x68, 0x00])
        dt = ((resp[0] << 8) + resp[1]) & 0x3FF
        v = dt / 1023 * 15.0
        print("BATTERY voltage: " + str("{:.2f}".format(v)))
        time.sleep(1)

    except KeyboardInterrupt:
        spi.close()
        sys.exit()