Below is some detail regarding the latest project I have been working on. Which is near completion.
I plan to wire it up permanently, place within a case and wall mount it.

Some of the images don’t come up too great in the video, I have included the actual images used here;

I created a simple one line bash script that polls for the temperature every 5 mins.

The main python program uses pygame to write to the TFT via a framebuffer and Matplotlib is used to create the Graphs.
The display can be changed by either the button on the breadboard or via the remote FOB.

What is being displayed;

• Current Time.
• Last recorded temperature.
• Rotate between time and temperature.
• Graph of recorded temperature for the last 12 hours.
• Graph of recorded temperature for the last 24 hours.
• Graph of recorded temperature for the last 7 days.

To prevent the SD card filling up with data, when started, the user will be prompted to delete data older then 7 days.

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Hardware used

• Raspberry Pi Rev 2: http://www.raspberrypi.org
• 1.8″ TFT from Adafruit; http://www.adafruit.com/products/358
• 315 MHZ RF receiver and FOB from Adafruit; https://www.adafruit.com/products/1096
• Tactile switch from Adafruit; https://www.adafruit.com/products/1010 (I love these switches, they work flawlessly and have a good feel.)
• Temperature sensor from Sparkfun; https://www.sparkfun.com/products/9418

Wiring

Temperature logging

The script that records the temperature every 5 minutes;

Here is the code

#!/usr/bin/python
from subprocess import *
import matplotlib
from  numpy import genfromtxt
matplotlib.use('Agg')
import pylab
import Image
import pygame
import os
import time
from time import strftime
#from pygame.locals import*
#from matplotlib.dates import DateFormatter
import RPi.GPIO as GPIO
import datetime
def run_cmd(cmd):
      """Used to run Linux commands"""
      p = Popen(cmd, shell=True, stdout=PIPE)
      output = p.communicate()[0]
      return output
def ckyorn( prompt):
    """Used for Y/N prompt"""
    while True:
        a=raw_input( prompt + " [y,n,?]: " ).upper()
        if a in [ 'Y', 'YES']: 
            return True
        elif a in [ 'N', 'NO']: 
            return False
def delete_old_data():
    """ Used to delete old data in input file. Will check for data older than 14 days
    and ask if you would like everything older than 7 days to be deleted. This should not being asked more than once a week"""
    now = datetime.datetime.now()
    #get the first line of the data file, which will be the oldest entry
    getfirst = run_cmd("head -1 temperature_logging | awk '{print $2}'")
    #convert string to time.
    firstLineTime = datetime.datetime.strptime(getfirst, '%m-%d-%Y-%H:%M:%S ')
    
    #Get the date and time for seven days ago from now.
    sevenDaysAgo = now - datetime.timedelta(days=7)
    sevenDaysAgoStr =  sevenDaysAgo.strftime('%m-%d-%Y-%T')
    #If the data and time in the first line is older than 14 days, ask if okay to delete.
    if (now - firstLineTime) > datetime.timedelta(days=14):
       	print ("More than 14 days worth of data has been collected.")
        if ckyorn ("Would you like to delete data older than 7 days?"):        
            sedCommand = "sed -n -i  '/" + sevenDaysAgoStr[1:15] + "/,$p' temperature_logging"
            run_cmd(sedCommand)
def displayText(text, size, line, color, clearScreen):
    """Used to display text to the screen. displayText is only configured to display 
    two lines on the TFT. Only clear screen when writing the first line"""
    if clearScreen:
        screen.fill((0, 0, 0))
        
    font = pygame.font.Font(None, size)
    text = font.render(text, 0, color)
    textRotated = pygame.transform.rotate(text, -90)
    textpos = textRotated.get_rect()
    textpos.centery = 80	
    if line == 1:
         textpos.centerx = 90
         screen.blit(textRotated,textpos)
    elif line == 2:
        textpos.centerx = 40
        screen.blit(textRotated,textpos)

def displayTime():
    """Used to display date and time on the TFT"""
    screen.fill((0, 0, 0))
    font = pygame.font.Font(None, 50)
    now=time.localtime()
   
    for setting in [("%H:%M:%S",60),("%d  %b",10)] :
         timeformat,dim=setting
         currentTimeLine = strftime(timeformat, now)
         text = font.render(currentTimeLine, 0, (0,250,150))
         Surf = pygame.transform.rotate(text, -90)
         screen.blit(Surf,(dim,20))

def graph(toKeep):
    """Used to display the graphs. Text will be shown before hand as
    the graphs take time to generate"""
    global firstTime
    imageFile = 'gp.png'
    #Display some text stating that graphs are being generated 
    if toKeep == TwelveHours:
        displayText('Creating', 35, 1,(200,200,1),True)
        displayText('12 Hour Graph', 32, 2,(150,150,255), False)
    elif toKeep == TwentyFourHours:
        displayText('Creating', 35, 1,(200,200,1), True)
        displayText('24 Hour Graph', 32, 2,(150,150,255), False)
    elif toKeep == OneWeek:
        displayText('Creating', 35, 1,(200,200,1), True)
        displayText('One Week Graph', 28, 2,(150,150,255), False)
    pygame.display.flip()
    #Get temperature and time data from data file
    temp = genfromtxt(dataFile, dtype=None, usecols=(0), skip_header = lines - toKeep)
    timecaptured = genfromtxt(dataFile, dtype=None, usecols=(1), skip_header = lines - toKeep)
    #Site the size of the font for the axis
    for label in ax.get_xticklabels():
        label.set_fontsize(8)
    for label in ax.get_yticklabels():
        label.set_fontsize(8)
    #Create xaxis labels and only show every 12th or 96th
    xlabels = range(toKeep)
    if toKeep == OneWeek:
        pylab.xticks(xlabels[::96], [v[:5:] for v in timecaptured[::96]])
    else:
        pylab.xticks(xlabels[::12], [v[11:16] for v in timecaptured[::12]])
        
    #Plot the graph
    pylab.plot(temp,linewidth=2, antialiased=True)
    #Change some colours
    ax.patch.set_facecolor('#FFFFCC')
    ax.patch.set_alpha(0.5)
    #Rotate the text in the xaxis
    fig.autofmt_xdate(rotation=90)
#    ax.xaxis.set_major_formatter( DateFormatter('%H:%M') )
    #Set the yaxsis limits
    pylab.ylim(0,40)
 
    #Save the graph as an image and the re-open it, rotate it and then display to TFT.
    pylab.savefig(imageFile, facecolor=fig.get_facecolor(),bbox_inches='tight', dpi=80,pad_inches=0.03)
    pil_im = Image.open(imageFile)
    pil_out = pil_im.rotate(-90)
    pil_out.save(imageFile)
    img = pygame.image.load(imageFile)
    screen.blit(img,(0,0))
    pygame.display.flip()
    #Clear graph data in preparation for next plot
    pylab.cla()
    #Reset the firstTime Variable
    firstTime = 0

   
def main():
  global ax,fig,screen
  global firstTime,lines
  global TwentyFourHours,TwelveHours,OneWeek
  global dataFile
  dataFile = 'temperature_logging'
  size = width, height = 128, 160
  TFTxSize = 2.28
  TFTySize = 1.63
  TwentyFourHours = 288
  TwelveHours = 144
  OneWeek = 2016
  firstTime = True		#Used to work out if a function has already been run
  whatToDisplay = 1		#What do display on screen
  rotate = 1   			#Used when automatically rotating the display.
  startTime = time.time()	#Used to work out how much time has passed when rotating.
  #Set the framebuffer device to be the TFT
  os.environ["SDL_FBDEV"] = "/dev/fb1"
  #Setup pygame display
  pygame.init()
  pygame.mouse.set_visible(0)
  screen = pygame.display.set_mode(size)

  #Setup plot area
  fig = pylab.figure()
  ax = fig.add_subplot(111)
  fig.set_size_inches(TFTxSize, TFTySize)
  background = pygame.Surface(screen.get_size())
  background = background.convert()

  #Setup GPIO
  GPIO.setmode(GPIO.BCM)
  GPIO.setup(17, GPIO.IN) #Read GPIO 17 as input

  #Open data file and count how many lines
  file = open(dataFile)
  lines = sum(1 for word in file if "." in word)
  file.seek(0,0)

  delete_old_data()
  while True:
      time.sleep(.5)
      """Check to see if button is pressed, and if so, increment by  one
      or reset to one if over 6"""
      if GPIO.input(17):
          whatToDisplay = 1+(whatToDisplay%7) #Rotate between 1 and 6
	  firstTime = True      #If button pressed, set this to True
      if whatToDisplay == 1:    #Display time
          displayTime()
      elif whatToDisplay == 2:  #Display last temperature recorded.
          file.seek(-26,2)      #Go to end of data file to get temperature
          currentTemp = file.readline(5) + ' \xb0C'
          displayText('Current Temp', 30, 1, (200,200,1), True )
          displayText(currentTemp, 50, 2, (150,150,255), False )
      elif  whatToDisplay == 4 and firstTime:
          graph(TwelveHours)
      elif  whatToDisplay  == 5 and firstTime:
          graph(TwentyFourHours)
      elif  whatToDisplay == 6 and firstTime:
          graph(OneWeek)
      elif  whatToDisplay == 3:	#Rotate display
          elapsedTime = time.time() - startTime
          if elapsedTime > 5:
              rotate = not rotate
              startTime = time.time()
          if rotate:
              file.seek(-26,2)
              currentTemp = file.readline(5) + ' \xb0C'
              displayText('Current Temp', 30, 1, (200,200,1), True )
              displayText(currentTemp, 50, 2, (150,150,255), False )
          elif not rotate:
                  displayTime()
      #Write to TFT
      pygame.display.flip()
		
	
if __name__ == '__main__':
    main()

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