BooKlock

This is a post from ~3 years ago on my old website that I’m now reposting.

Looking back, I probably shouldn’t have stuck the Nook inside of a book. It looks terrible.

I made a literary clock (conceptually based on the one by Jaap Meijers) using an old Nook Simple Touch housed inside an hollowed-out book. This “booklock” stores quotes from various novels that mention times of day and it displays the time using a random quote corresponding to the current minute. For example, in the picture above a quote is signifying that the time was 1:30 when the picture was taken.

Hacking e-readers is known as “rooting”. E-readers typically run a version of Android behind the scenes and rooting the e-reader allows one to access the functions of the Andoid OS with root privilages. Meijers used the “eips” command available on rooted Kindles to write quotes to the screen. Unfortunately, the Nook has no such command built-in. I was thus forced to display the quotes as screensaver images. I accomplished this by having a cron job that runs every minute trigger a shellscript that checks the time, unhides an appropriate quote image file in the screensaver directory of the Nook, and then enters a software-emulated keystroke that wakes the kindle and immediately resleeps it in order to switch the screensaver to the right quote for the current time.

A total hack? Well…yeah. It works like a charm though, and uses minimal battery.

Here’s how you can make you’re own literary clock out of a Nook Simple Touch: Step 1: Rooting the Nook

You’re Nook Simple Touch (NST) can be rooted using the NookManager software and instructions here on this XDA Developers forum thread. I won’t bother guiding through the process since it’s explained in many other articles online. Just search up “root nook simple touch”.

Once you’ve rooted the NST, enable ADB using the ADB Konnect app (and connect to wifi of course). Access the NST’s shell using adb on your computer using the commands “adb connect <IP.ADDRESS.OF.NST>” and “adb shell”. The NST does not already have a cron service, so you must install the Cron4Phone app APK on the NST (it can be downloaded from this thread) using the command “abd install cron4phone.apk”. Step 2: Adding the Clock Script and Quotes

To install the script that will run the clock, plug your NST into a computer and open the device that shows up in your file browser. Then unzip the contents of the “booklock” folder in this zip into the screensaver folder on your Nook. The “times” folder contains all the images corresponding to each minute. Each image file has a period in front of the filename to stop it from being displayed. In *nix systems, a period in front of a filename hides the file. The booklock.sh file is the script that will check the time and unhide the appropriate image by renaming it to not have a period in front of the name.

In order to have booklock.sh run every minute, we need to add it as a job in the Cron4Phone app. Open the Cron4Phone app and navigate to Tasks. Add a new task or edit an existing one. In the task editor, change the command to “sh /media/screensavers/bookclock.sh” and the schedule to be “* * * * *”. Five asterisks means “Run every minute, every hour, every day, every month, every day-of-the-week”. Check the option to enable the task and to autostart on boot.

At this point, the booklock should work! Wait a minute and the screen should go to sleep and display a quote with the time. If it flashes, but does not go to sleep, press the power button to put it to sleep. Step 3: House the NST

Now that we have a functioning clock, we’ve got to give it a proper home. I stuck mine in a hollowed out book. I cut, starting around the middle of the the book, an approximate sillouhette of the Nook deep enough to put the Nook in. Then I glued those pages together so they wouldn’t move around. Then I took a couple of the pages in front of those pages, cut out just enough to see the Nook’s screen, and glued those to each other to make a flap with a window in it. This allowed me to place the Nook in the deep hollowed portion and then close the flap over it. I added velcro to the Nook and the flap so that they could be stuck to each other. The power cord for the Nook was routed through the botton between the pages and a hole was drilled in the back of the book so that the power button could be pressed by sticking a pen through the hole. Conclusion

I hope you enjoy your booklock! Literary clocks are a wonderfully nerdy and stylish way of telling time.