我给舵机设定转动一定的角度，舵机就会一直抖动.

from machine import I2C
from vl53l1x import VL53L1X
import time
from pyb import UART

i2c = I2C(2)
distance = VL53L1X(i2c)

uart = UART(3, 115200)

while True:
print("range：mm ",distance.read() )
uart.writechar(distance.read())
time.sleep(1000)

@kidswong999 为什么我把tof测出的距离通过串口输出会报错？