I've been blogging about my experiences in Road Test reviewing the Ultimate Raspberry Pi Bundle. As a part of this Road Test I'm creating a Fridge/Freezer Temperature Alarm system for our local food shelf. You can see where this Road Test started for me here
My next step is to add an LCD display connection
I have two choices with the The Ultimate Raspberry Pi Bundle
I'm going to start with the PiFace Control & Display because it doesn't need to be soldered together and it features an interesting Remote Control interface. I'm glad that both items include the option of control buttons (should be handy for adjusting the temperature sensor and for use as a "snooze alarm" button for my Temperature Alarm System.
The PiFace™ Control & Display is a plug and play device that allows you to use and control your Raspberry Pi without a keyboard, mouse and monitor. It saves space and power yet still provides a simple and functional user interface.
This document walked me through the simple process of
- aligning the CAD shield and connecting it to the Pi
- Enable the SPI bu by running: sudo raspi-config, option 5
- the installation of Control and Display software by running
sudo apt-get install python3-pifacecad
- Testing the device with the handy sysinfo.py command
Note: the sysinfo.py example command shows the IP address and temperature of the Raspberry Pi. Having the IP address is handy for times when I want to use SSH to start vncserver and then vncviewer to connect to the system
I put the Pi away and when I came back to try it again the next day. To my surprise, sysinfo.py made the screen flicker but display nothing. The troubleshooting section in Quick Start Guide mentioned :
If your LCD has nothing appearing on it or its character spaces are all
black, try adjusting the contrast screw with a small star head screwdriver.
But it doesn't exactly say where that is...look for the screwdriver in the lower right hand corner of the picture...that's where the adjustment screw is:
One question I have is with the CAD in place, how can I easily access the other ports available, ...looks like they are available on top??
Wake Up with Sysinfo!
As I mentioned in my last post I like connecting to my Pi using vnc and in the interest of learning something new, I decided to have the sysinfo program run at startup for my Pi. This way no matter where I plug it...it will display the IP address it has been assigned and then I can easily SSH to it (and optionally run vncserver)
In order to make sysinfo.py run at startup, I had to:
- Copy the sysinfo.py program to sysinfo1Time.py and modify it so that it no longer loops forever.
- register the sysinfo1Time.py program so it runs at startup
To modify sysinfo.py script so it no longer loops forever, you simply need to:
- comment out line 48, the while True statement in the show_sysinfo() routine.
- comment out line 57, the while Sleep statement in the show_sysinfo() routine.
- change the indentation on the show sysinfo() routine
To Run the sysinfo1Time.py at startup, you simply need to:
- create a file in /etc/init.d that calls the new sysinfo1Time.py script (I've called it SysInfostart and attached it to this blog post)
- chmod +x /etc/init.d/SysInfostart
- test running the script so it won't hang or error out at reboot
- register the command to run at startup by running the command:
sudo update-rc.d SysInfostart defaults
- Should you want to stop having this program run at startup run the following command:
sudo update-rc.d -f SysInfostart remove
Now reboot the Raspberry Pi and you'll see "Waiting for IP...." and then the IP Address of your Pi will appear
To use VNC to connect to the Pi you simply need to:
- run ssh or putty from your windows machine to the ip address. An easy way to do this is to install Winscp and use it
Once you log on to the Pi with WinScp, click on the ,Open Terminal icon and you can run commands on the system...in this case we want to run the vncserver command
And finally you'll be able to connect using vncviewer.
Vncviewer gives you a full gui environment running on the Pi
Next steps for me on the Ultimate Raspberry Pi Bundle review........create something useful with the PiFace Control & Display....it's called the Automatic One-Liner Machine
Also ...things to look into...I found if I want to try to debug the problem with my XBMC SD card, I should take a look at this page R-Pi Troubleshooting - eLinux.org