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Using my 1.8 TFT as a Raspberry Pi status display

I have been experimenting with my Raspberry Pi TFT display these few days with the intention to use it as a misc status display, heavily influenced by Mark‘s work. I collect most of my house’s telemetrics to an emoncms installation running on the server where I host this blog, so I will pull some of the data I need to visualize from there. I would be showing information such as

  • Room temperatures (transmitted by multiple Funky+DS18B20)
  • Outside air temperature and humidity (measured with Funky+DHT22)
  • Heat pump telemetrics (power consumption, multiple temperature measurements as described here)
  • House power consumption as described here 
  • Solar hot water tank telemetrics (gathered as explained here and here)
  • Misc weather data from Weather Underground, data collected using the method I explained here

The python script is pretty self-explanatory, it uses pygame to generate the screens on the framebuffer device. This is work in progress, I will expand the script with IR remote control with Funky, so I can chose which specific page to show or other functions that I haven’t decided on yet.

I think that pulling and displaying satellite weather data from Weather  Undergound for my area is pretty cool too:



Another cool part is displaying overlayed emoncms data for outside/ room temperatures and heat pump power usage as per my post here; I use a slightly simplified chart sized down to 160×128 pixels and display that one too:


tempdata No room for legends but I already know the colors by heart 🙂

Yet another cool thing is to overlay weather icons on the outside temperature page, using Weather Undergound API to get actual icon:


The code


import pygame
import sys
import time
from time import strftime
import os
import httplib
import urllib
import json


#Set the framebuffer device to be the TFT
os.environ["SDL_FBDEV"] = "/dev/fb1"

#Get emoncms feed latest data
def getFeedVal(feedId):
	conn = httplib.HTTPConnection("*******SITE**********")
	conn.request("GET", "/emoncms3/feed/value.json?apikey=*******API**********&id=" + feedId)
	response = conn.getresponse()
	#print response.status, response.reason
	data =
 	return data

def getWUnder():
	global time_stamp_prev
	# Only fetch latest data once every while, or we will violate WU's rules
	if (time.time() - time_stamp_prev) > 15*60:
		time_stamp_prev = time.time()
		f = urllib.urlopen('*******W.U. key**********/geolookup/conditions/q/sofia.json')
		json_string =
		parsed_json = json.loads(json_string)
		#temp_c = parsed_json['current_observation']['temp_c']
		#print "Current temperature in %s is: %s" % (location, temp_c)
		#Also see
		iconurl = parsed_json['current_observation']['icon_url']
		urllib.urlretrieve (iconurl, "graph.gif")

		urllib.urlretrieve ("*******W.U. key**********/satellite/q/KS/Sofia.gif?width=160&height=128&basemap=1","satellite.gif")

def displayTime():
#    """Used to display date and time on the TFT"""
    font = pygame.font.Font(None, 50)

    for setting in [("%H:%M:%S",60),("%d  %b",10)] :
         currentTimeLine = strftime(timeformat, now)
         text = font.render(currentTimeLine, 0, (0,250,150))
         Surf = pygame.transform.rotate(text, -90)

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
    elif line == 2:
        textpos.centerx = 40

def main():
	global screen

	size = width, height = 128, 160
	black = 0, 0, 0

	screen = pygame.display.set_mode(size)

#HP boiler=11
#Solar boiler=16
#Living room t=76
#Kids room t=18
#Outside temp=71
#Outside humidity=70

	while True:



		displayText('Outside Temp', 30, 1, (200,200,1), True )
		displayText(getFeedVal("71") + "C", 50, 2, (150,150,255), False )

		graph = pygame.image.load("graph.gif")
		graph = pygame.transform.rotate(graph, 270)
		graphrect = graph.get_rect()
		screen.blit(graph, graphrect)


	 	displayText('Out. Humidity', 30, 1, (200,200,1), True )
		displayText(getFeedVal("70") + "%", 50, 2, (150,150,255), False )

	 	displayText('Solar boiler', 30, 1, (200,200,1), True )
		displayText(getFeedVal("16") + "C", 50, 2, (150,150,255), False )

	 	displayText('HP Boiler', 30, 1, (200,200,1), True )
		displayText(getFeedVal("11") + "C", 50, 2, (150,150,255), False )

		urllib.urlretrieve ("http://******* path to my site**********.php", "graph.png")
		graph = pygame.image.load("graph.png")
		graph = pygame.transform.rotate(graph, 270)
		graphrect = graph.get_rect()
		screen.blit(graph, graphrect)

		graph = pygame.image.load("satellite.gif")
		graph = pygame.transform.rotate(graph, 270)
		graphrect = graph.get_rect()
		screen.blit(graph, graphrect)

if __name__ == '__main__':

To autostart the script on boot I did

sudo nano /etc/init.d/tft

and the tft script goes like this:

#! /bin/sh

# If you want a command to always run, put it here

# Carry out specific functions when asked to by the system
case "$1" in
    echo "Starting TFT status display.."
    sudo python /home/pi/python/ &
    echo "Stopping TFT.."
    killall python
    exit 1

Finally, these commands will register your script to run at boot and shutdown:

sudo chmod +x  /etc/init.d/tft
sudo update-rc.d tft defaults

2 thoughts on “Using my 1.8 TFT as a Raspberry Pi status display

  1. Pingback: Thomas Höser » Project: 1.8 TFT Raspberry Pi Status Display

  2. Borreltje

    Hi Martin,
    I found your script and wanted to use just some parts of it, I want the weather on my display, so I deleted the unwanted bits from your script, now it just displays the time and date and after 10 sec it should give the temp with weather icon.
    I see the time on the screen, but it does not flip over to the weather?
    If I uncomment the line that says: print “Current temperature in Someren is: %s” % (temp_c) I get that line in my terminal, but not on screen.
    Are you willing to help me out? can I post the script here or send it to you via email?

    thanks for the sharing your script anyway, I allready some useful things from it.

    kind regards,
    Bor van Gool