BeagleBone Black Interfacing: hardware and software [Kindle Edition]

http://www.amazon.com/BeagleBone-Black-Interfacing-hardware-software-ebook/dp/B00Q1E381M/ref=sr_1_1?ie=UTF8&qid=1418789675&sr=8-1&keywords=BeagleBone-Black-Interfacing-hardware-software-ebook

SD Card Image Available

I've made my SD Card image available on DropBox. 

https://www.dropbox.com/sh/0k5tylfsyubjuoc/AACIjd9ZLYGbBBoVqQDIYr9ma?dl=0


The file is split into 10MB chunks, so use 7-Zip to join and uncompress the .img file.

Use Win32DiskImager to write the image to a 2G or larger SD card.

Use GParted (in Linux) to increase the data partition size so it uses all the SD cards available storage.

Changing Local Time Zone on BBB running Debian 7 (Wheezy)

If you don't want to use UTC time then here are the steps to change it.
The changes should be instantaneous and don't require a reboot.

You may need to do this for all user accounts.

1. dpkg-reconfigure tzdata (select your timezone)
2. Edit /etc/adjtime and change the last line from UTC to LOCAL

Beaglebone Black microSD Imaging, Re-Sizing and Booting

I wanted to to install Debian on a larger drive, so we had a camera that expired which had a 16GB microSD card in it that I re purposed.

The following is what I did to get a 16GB Debian drive on my BBB and should work for larger drives too.

Imaging the microSD Card (http://beagleboard.org/getting-started#update)

First we need to install the OS image we want to run on the BBB to our microSD card. The steps are as follows:

1. Get the latest image from here: http://beagleboard.org/latest-images
2. Grab Win32DiskImager 
3. Using 7Zip unzip the compressed image downloaded in step 1
4. Insert the larger microSD card in your computer. You probably need a microSD to SD adapter.
5. Start Win32DiskImager
6. Press the blue folder icon located to the right of the Image File text box
7. Select the microSD card to image using the Device pull-down menu
8. When you are ready to image the microSD card press the Write button
9. This process should take several minutes

Extend the 2GB Partition

Since the OS image is sized for a 2GB SD card and we're installing it on a larger SD card we need to extend the data partition to include the unallocated space on the SD card.  To accomplish this you will need vncserver running as root on the BBB. GParted is the program we will use to extend the filesystem which we will need to install.

1. Install gparted (apt-get install gparted) on the BBB
2. VNC into BBB
3. Press the Debian start button (lower left corner) and select Run
4. Type in gparted 
5. Detailed instructions -  Step3 on how to use GParted
6. Select the SD card to re-size under devices (upper right)
7.  Select the ext4 partition on the graph
8. Right click and select Resize/Move
9. With the mouse grab the right side of the partition block and drag it all the way to the right
10. Press the Resize/Move button
11. Press the green check mark icon
12. Acknowledge the resize action
13. This action will take a few minutes... do not close gparted or shutdown BBB until it completes

Booting the BBB from the microSD Card

1. With the BBB powered off insert the microSD card into the slot
2. Press and hold the tiny button nearest the microSD card
3. Apply power to the BBB
4. Once all 4 LEDs light up release the tiny button nearest the SD card
5. The BBB should now be running the OS from the microSD card

Updating the System

1. Log in as root via Putty (you will get a certificate security warning)
2. Make sure you have internet connectivity
3. Run: apt-get update
4. Run: apt-get upgrade

You should now have your OS installed on and booted from a larger drive.

You can also use Win32DiskImager to create an image file of the larger SD card for back up purposes.  Install any applications you desire on the new larger drive and then use Win32DiskImager to back the image up saving you from installing from scratch if the SD card ever fails.  Remember to back up the SD card image after any major changes so you don't have to re-complete them.

Until next time,

Cheers!

Brew Chamber Controller (Feature Requests)

If you have a feature request you would like to see in bcc.py then add a comment below.

Remember, currently this is a one man operation and I can only go as fast as I can in my spare time; Considering this feature may not be added depending on the number of requested features and their priority.

Designing a Brew Chamber Controller (Update 11)

Latest version 0.07.0a available on GitHub.

https://github.com/cyberlord8/bcc

#0.07.0a (07 NOV 2014)
- Added gnuplot charting of avg temperature
- Added date time to bcc.py display
- Updated user manual

Screen shot:

 

Designing a Brew Chamber Controller (Update 10)

bcc.py soon to have graphing capabilities.

I've been playing with gnuplot and have bcc.py outputting a gnuplot script and a datafile to chart.

Seems to be working well, now to tidy up a bit and add a command to turn this feature on and off.

It will be available in the next release so stay tuned.

Simulated Fermentation

Designing a Brew Chamber Controller (Update 9)

Latest version 0.06.0a available on GitHub.

https://github.com/cyberlord8/bcc

Version History
~~~~~~~~~~~~~~~

#0.06.0a (31 Oct 2014)
- Fixed minor display bug with alarm status display when SMS texts were sent
- Fixed bug where sometimes the high temp alarm was on but the cooler was not
- Added cell phone number to settings file instead of hard coded in software
- Settings file is now written to every time a command is entered in case the program crashes
- Added database (database.csv) that stores current system status every 15 minutes
- Added brew information - preparation for auto brew process

Screen Shot:

Beta Testers Wanted

Looking for beta candidates to test the bcc.py software.

Requirements:

1. Must have a Beaglebone Black Rev C running Debian distro.
2. Must have two 3.3 volt 10A or better solid state relays (SSR) or two PowerSwitch Tails
3. Must be able to install the required libraries and support software on the BBB and laptop/computer
4. Must be able to use GitHub repository to install (clone) the bcc code on your BBB
5. Must provide detailed bug reports and how to recreate the bug on GitHub
6. A good working knowledge of linux command and GUI interfaces is preferred
7. Programming knowledge is not required but would like a few knowledgeable Python programmers 
8. A few novices/beginners may be selected to help write detailed setup and operation instructions

 If you are interested please reply with a comment to this post.

Thanks,

My BBB Projects

Designing a Brew Chamber Controller (Update 8)

Latest version 0.05.0a available on GitHub.

https://github.com/cyberlord8/bcc

Version History
~~~~~~~~~~~~~~~
#0.05.2a - Added a user manual #0.05.1a
- Fixed bug in bcc.desktop that made the terminal window too small to display bcc properly
#0.05.0a
- Yeast profiles added - can now read in yeast database and select a yeast by it's ID number
- Modified the alarm system and added SMS texting of alarm status every hour (enter YOUR OWN phone number!!!)

Designing a Brew Chamber Controller (Update 7)

Latest version 0.04.0a available on GitHub.

https://github.com/cyberlord8/bcc

Version History

~~~~~~~~~~~~~~~

#0.04.0a

- Fixed bug where the different brew cycles were not calculating properly due to global variable not being declared

- bcc now saves current settings to a file (bccconfig.py)

- Increased precision in F/C conversion formulas which was causing a rounding error

- Added reset min and max temp variables function (ability to reset them for each brew session?)

- Added GPL 3.0 license verbiage

- Fixed bug where cycling brew cycle off and on would cause compressor to turn on and off with no 5 minute delay

Designing a Brew Chamber Controller (Video Update)

Video of bcc.py in action.

http://youtu.be/g_0-PoQFZpM

Designing a Brew Chamber Controller (Update 6)

A few screen shots of version 0.03a. The system is currently residing in my entertainment center so that is why the temperature readings are so warm.

This is the self test code where the LEDs are lit and the thermistor is checked to see if it reads a sensible value.

The initial startup screen where we are waiting for the average temperature to stabilize.

Once the average temperature stabilizes the system starts in the 'Off' mode.

The warm cycle is used to start the fermentation process. Once it gets underway the cycle is changed to normal cycle.

The normal cycle is used for the primary fermentation. Once the primary is complete a cold crash cycle is used to drop the suspended yeast faster.

The lager cycle is used for lagering a beer.

Cold crash is used to drop the yeast quickly.

Clear cycle can be used to age or secondary a beer.

Designing a Brew Chamber Controller (Update 5)

I've also updated the trend function.  I wanted to incorporate Object Oriented Programming OOP into the codebase and go full OOP in the final GUI version so I started on the trend function which is of no importance to the operation of the program in case I screwed it up :).

The main program loop calls the Trend Class  method move_averages(). Move_averages stores the last 4 temperature readings.  It then calls the set_average and set_trend methods. These methods store the average temperature over the last minute, and the trend.  These values are then accessible from other functions, for example, if we had an object called trending that was of the class Trend, we could access the average temperature and trend by calling trending.moving_avg_temp and trending.trend respectively.

The complete code can be found at: https://github.com/cyberlord8/bcc

#Trend Class##############################################
#calculates whether temp went up or down or stayed the same since last checked
#may make this an averaging function so we check the current temp compared to last # averages

class Trend:

  def __init__(self):#######################

    #initialize static variables
    self.trend ="-"
    self.moving_avg_temp = 0
    self.temp1 = 0
    self.temp2 = 0
    self.temp3 = 0
    self.temp4 = 0

    return


  def move_average(self):#Called every 15 seconds from main program loop#

    #move the temperatures through the 4 variables
    #since this is updated every 15 seconds there is one minute of data stored here
    self.temp4 = self.temp3
    self.temp3 = self.temp2
    self.temp2 = self.temp1
    self.temp1 = current_temperature

    self.set_average() #average the 4 values
    self.set_trend() #set the trend indicator

    return


  def set_trend(self):######################

    if current_temperature > self.moving_avg_temp+.01: self.trend = "^" #upward trend
    elif current_temperature < self.moving_avg_temp-.01: self.trend = "v" #downward trend
    else: self.trend = "-"
   
    return


  def set_average(self):###################

    self.moving_avg_temp = (self.temp1 + self.temp2 + self.temp3 + self.temp4) / 4

    return