I2C接口与超声测距

i2c_range_smbus.py

'''ultrasonic ranging using I2C'''
'''software tools : smbus'''
'''hardware       : KS103    '''

import smbus
import time

bus = smbus.SMBus(1) #open /dev/i2c-1
address = 0x74 #i2c device address
wr_cmd = 0xb0  #range 0-5m, return distance(mm)
#rd_cmd = 0xb2 
##range 0-5m, return flight time(us), remember divided by 2
try:
    while True:
        bus.write_byte_data(address, 0x2, wr_cmd)
        time.sleep(1) #MIN ~ 0.033
        HighByte = bus.read_byte_data(address, 0x2)
        LowByte = bus.read_byte_data(address, 0x3)
        Dist = (HighByte << 8) + LowByte
        print('Distance:', Dist/10.0, 'cm')
        #time.sleep(2)
except KeyboardInterrupt:
    pass
bus.close()
print('Range over!')

i2c_range_pigpio.py

'''ultrasonic ranging using I2C'''
'''software tools : pigpio'''
'''hardware       : KS103    '''

import pigpio
import time

pi = pigpio.pi()
if not pi.connected:
    exit()
address = 0x74 #i2c device address
h = pi.i2c_open(1,address) #open device at address on bus 1
wr_cmd = 0xb0  #range 0-5m, return distance(mm)
#rd_cmd = 0xb2 
##range 0-5m, return flight time(us), remember divided by 2
try:
    while True:
        pi.i2c_write_byte_data(h, 0x2, wr_cmd)
        time.sleep(1) #MIN ~ 0.033
        HighByte = pi.i2c_read_byte_data(h, 0x2)
        LowByte = pi.i2c_read_byte_data(h, 0x3)
        Dist = (HighByte << 8) + LowByte
        print('Distance:', Dist/10.0, 'cm')
        #time.sleep(2)
except KeyboardInterrupt:
    pass
pi.i2c_close(h)
print('Range over!')

i2c_range_wiringpi.py

'''ultrasonic ranging using I2C'''
'''software tools : wiringpi'''
'''hardware       : KS103    '''

import wiringpi as wpi

address = 0x74 #i2c device address
h = wpi.wiringPiI2CSetup(address) #open device at address
wr_cmd = 0xb0  #range 0-5m, return distance(mm)
#rd_cmd = 0xb2 
##range 0-5m, return flight time(us), remember divided by 2
try:
    while True:
        wpi.wiringPiI2CWriteReg8(h, 0x2, wr_cmd)
        wpi.delay(1000) #unit:ms  MIN ~ 33
        HighByte = wpi.wiringPiI2CReadReg8(h, 0x2)
        LowByte = wpi.wiringPiI2CReadReg8(h, 0x3)
        Dist = (HighByte << 8) + LowByte
        print('Distance:', Dist/10.0, 'cm')
except KeyboardInterrupt:
    pass
print('Range over!')

i2c_temp.py

'''tempature measure using I2C'''
'''software tools : smbus'''
'''hardware       : KS103    '''

import smbus
import time
import sys

bus = smbus.SMBus(1) #open /dev/i2c-1
address = 0x74 #i2c device address
wr_cmd = [0xc9, 0xca, 0xcb, 0xcc]  #tempature measurement cmd
precision = [0.5, 0.25, 0.125, 0.0625] # tempature measurement precision 
#rd_cmd = 0xb2 
##range 0-5m, return flight time(us), remember divided by 2
try:
    print('Please input number 0~3 to select tempature measurement precision. ')
    print('0 : 0.5℃,')
    print('1 : 0.25℃,')
    print('2 : 0.125℃,')
    print('3 : 0.0625℃,')
    cmd_num = eval(input('Input number:'))
    if(cmd_num not in [0,1,2,3]):
        print('Input error!')
        sys.exit()
    print('precision selected:',precision[cmd_num])
    cmd = wr_cmd[cmd_num]
    while True:
        bus.write_byte_data(address, 0x2, cmd)
        time.sleep(1) #MIN ~ 0.061
        HighByte = bus.read_byte_data(address, 0x2)
        LowByte = bus.read_byte_data(address, 0x3)
        data = (HighByte << 8) + LowByte
        if(HighByte >= 0xF8):
            data = data - 65536 #2**16
        Temp = data * 0.0625
        print('Tempature:', Temp, '℃')
        #time.sleep(2)
except KeyboardInterrupt:
    pass
bus.close()
print('The end!')