raspberry pi (12) I2C LCD1602液晶显示器，DS1302事实时钟
1.I2C LCD1602液晶显示器
#!/usr/bin/env python
import time
import smbus
BUS = smbus.SMBus(1)
def write_word(addr, data):
global BLEN
temp = data
if BLEN == 1:
temp |= 0x08
else:
temp &= 0xF7
BUS.write_byte(addr ,temp)
def send_command(comm):
# Send bit7-4 firstly
buf = comm & 0xF0
buf |= 0x04 # RS = 0, RW = 0, EN = 1
write_word(LCD_ADDR ,buf)
time.sleep(0.002)
buf &= 0xFB # Make EN = 0
write_word(LCD_ADDR ,buf)
# Send bit3-0 secondly
buf = (comm & 0x0F) << 4
buf |= 0x04 # RS = 0, RW = 0, EN = 1
write_word(LCD_ADDR ,buf)
time.sleep(0.002)
buf &= 0xFB # Make EN = 0
write_word(LCD_ADDR ,buf)
def send_data(data):
# Send bit7-4 firstly
buf = data & 0xF0
buf |= 0x05 # RS = 1, RW = 0, EN = 1
write_word(LCD_ADDR ,buf)
time.sleep(0.002)
buf &= 0xFB # Make EN = 0
write_word(LCD_ADDR ,buf)
# Send bit3-0 secondly
buf = (data & 0x0F) << 4
buf |= 0x05 # RS = 1, RW = 0, EN = 1
write_word(LCD_ADDR ,buf)
time.sleep(0.002)
buf &= 0xFB # Make EN = 0
write_word(LCD_ADDR ,buf)
def init(addr, bl):
# global BUS
# BUS = smbus.SMBus(1)
global LCD_ADDR
global BLEN
LCD_ADDR = addr
BLEN = bl
try:
send_command(0x33) # Must initialize to 8-line mode at first
time.sleep(0.005)
send_command(0x32) # Then initialize to 4-line mode
time.sleep(0.005)
send_command(0x28) # 2 Lines & 5*7 dots
time.sleep(0.005)
send_command(0x0C) # Enable display without cursor
time.sleep(0.005)
send_command(0x01) # Clear Screen
BUS.write_byte(LCD_ADDR, 0x08)
except:
return False
else:
return True
def clear():
send_command(0x01) # Clear Screen
def openlight(): # Enable the backlight
BUS.write_byte(0x27,0x08)
BUS.close()
def write(x, y, str):
if x < 0:
x = 0
if x > 15:
x = 15
if y <0:
y = 0
if y > 1:
y = 1
# Move cursor
addr = 0x80 + 0x40 * y + x
send_command(addr)
for chr in str:
send_data(ord(chr))
#!/usr/bin/env python
import LCD1602
import time
def setup():
LCD1602.init(0x27, 1) # init(slave address, background light)
LCD1602.write(0, 0, 'Hello world')
LCD1602.write(0, 1, 'Raspberry Pi')
time.sleep(2)
def destroy():
pass
if __name__ == "__main__":
try:
setup()
while True:
pass
except KeyboardInterrupt:
destroy()
2.DS1302事实时钟
#!/usr/bin/python
from datetime import datetime
import ds1302
class DS1302:
def __init__(self, rangechecks=True):
self.rangechecks = rangechecks
ds1302.init_clock()
def get_datetime(self):
if not self.check_sanity():
# if clock are insane: try to reset it
self.reset_clock()
# if clock are still insane: return None
if not self.check_sanity():
return None
year, month, date = ds1302.get_date()
hour, minute, second = ds1302.get_time()
if self.rangechecks:
if year < 2000 or year > 3000:
ds1302.set_date(2000, month, date)
return self.get_datetime()
if month not in range(1, 13):
ds1302.set_date(year, 1, date)
return self.get_datetime()
if date not in range(1, 32):
ds1302.set_date(year, month, 1)
return self.get_datetime()
if hour not in range(0, 24):
ds1302.set_time(0, minute, second)
return self.get_datetime()
if minute not in range(0, 60):
ds1302.set_time(hour, 0, second)
return self.get_datetime()
if second not in range(0, 60):
ds1302.set_time(hour, minute, 0)
return self.get_datetime()
return datetime(year, month, date,
hour, minute, second)
def set_datetime(self, dt):
if not self.check_sanity():
# if clock are insane: try to reset it
self.reset_clock()
# if clock are still insane: return False
if not self.check_sanity():
return False
ds1302.set_date(dt.year, dt.month, dt.day)
ds1302.set_time(dt.hour, dt.minute, dt.second)
return True
def check_sanity(self):
"check sanity of a clock. returns True if clock is sane and False otherwise"
year, month, date = ds1302.get_date()
hours, mins, secs = ds1302.get_time()
if year == 2000 or month == 0 or date == 0:
return False
if secs == 80:
return False
return True
def reset_clock(self):
ds1302.reset_clock()
def format_time(dt):
if dt is None:
return ""
fmt = "%m/%d/%Y %H:%M:%S"
return dt.strftime(fmt)
def parse_time(s):
fmt = "%m/%d/%Y %H:%M"
return datetime.strptime(s, fmt)
#!/usr/bin/env python
#-----------------------------------------------------
#
# This is a program for DS1302 RTC Module.
# It provide precision timmer.
#
# This program depend on rpi_time.py.
#
# ds1302 Module Pi
# VCC ------------------ 5 V (Must be 5v)
# GND ------------------ GND
# SCL ---------------- Pin 16
# SDA ---------------- Pin 18
# RST ---------------- Pin 22
#
#-----------------------------------------------------
from datetime import datetime
import ds1302
import rpi_time
import time
import LCD1602
rtc = rpi_time.DS1302()
def setup():
print ''
print ''
print rtc.get_datetime()
print ''
print ''
a = raw_input( "Do you want to setup date and time?(y/n) ")
if a == 'y' or a == 'Y':
date = raw_input("Input date:(YYYY MM DD) ")
time = raw_input("Input time:(HH MM SS) ")
date = date.split()
time = time.split()
print ''
print ''
ds1302.set_date(int(date[0]), int(date[1]), int(date[2]))
ds1302.set_time(int(time[0]), int(time[1]), int(time[2]))
dt = rtc.get_datetime()
print "You set the date and time to:", dt
LCD1602.init(0x27, 1) # init(slave address, background light)
def loop():
while True:
a = rtc.get_datetime()
s = rpi_time.format_time(a)
print s
splits = s.split(' ')
print splits[0]
LCD1602.write(0, 0, splits[0])
LCD1602.write(0, 1, splits[1])
time.sleep(0.5)
def destory():
GPIO.cleanup() # Release resource
if __name__ == '__main__': # Program start from here
setup()
try:
loop()
except KeyboardInterrupt: # When 'Ctrl+C' is pressed, the child program destroy() will be executed.
destory()
