Raspberry Pi: How to show output from python on TFT display

Question

I'm trying to output some data from a python script to a Sainsmart 1.8 TFT display. Followed the instructions from https://github.com/notro/fbtft/wiki, I am able to show the raspberry's screen on the tft display with

FRAMEBUFFER=/dev/fb1 startx

When I try to output data from my python script, a pygame window ('pop up'-like) opens, but not on the tft screen, but on the main screen connected to the Raspberry with HDMI.

My code is from this tutorial:

#!/usr/bin/env python
# -*- coding: utf-8 -*-

#
# Creation:    26.05.2013
# Last Update: 07.04.2015
#
# Copyright (c) 2013-2015 by Georg Kainzbauer <http://www.gtkdb.de>
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#

import os
import sys
import time
import pygame

time_stamp_prev=0

os.environ["SDL_FBDEV"] = "/dev/fb1"
os.environ['SDL_VIDEODRIVER']="fbcon"

def displaytext(text,size,line,color,clearscreen):
  if clearscreen:
    screen.fill((255,255,255))

  font = pygame.font.Font(None,size)
  text = font.render(text,0,color)
  rotated = pygame.transform.rotate(text,-90)
  textpos = rotated.get_rect()
  textpos.centery = 80
  if line == 1:
    textpos.centerx = 99
    screen.blit(rotated,textpos)
  elif line == 2:
    textpos.centerx = 61
    screen.blit(rotated,textpos)
  elif line == 3:
    textpos.centerx = 25
    screen.blit(rotated,textpos)

def main():
  global screen

  pygame.init()
  pygame.mouse.set_visible(0)
  size = width,height = 128,160
  screen = pygame.display.set_mode(size)

  while True:
    displaytext(time.strftime("%d.%m.%Y"),40,1,(0,0,0),True)
    displaytext(time.strftime("%H:%M:%S"),40,2,(0,0,0),False)
    displaytext("www.gtkdb.de",20,3,(0,0,0),False)
    pygame.display.flip()
    time.sleep(1)

if __name__ == '__main__':
  main()

Can anyone tell me how to show the script's output on the tft screen?

Answer 1

I read on the startx command and a solution seems to me to create a .xinitrc file.

Try this:

chmod +x ./clock.py # make the clock file executable
mv ./clock.py ~/.xinitrc # move it to where startx starts it
FRAMEBUFFER=/dev/fb1 startx # startx will start it

Note: I tested this under Lubuntu and was still able to log in after this and use the user interface.