When I'm chairing a session at .Astronomy 8 or some other conference, I don't want to have to look at my watch. I want to just set a timer and the onus is on the speaker.

Use a blink(1) light to control your speakers when you are chairing a session.

You will need a blink(1) light and python. Is that too much to ask? (maybe)

The blink(1) library is only Python 3 compatible and PyUSB 1.0.0 release version has a bug in it. My advice to use a virtualenv with this. You set it up as follows

Using Anaconda

conda create -n blink python=3.4
source activate blink

Using virtualenv

virtualenv -p python3 env/blink
source env/blink/bin/activate

Then you can download this package and install with:

pip install talktimer-master/ # or whatever the directory name is that contains these files

After the package is installed you will have a command line script on your system path, which you can access from anywhere. If you installed with a virtual environment then you'll need to activate this first.

Example usage is:

are_you_still_talking --total 60 --warning 10 --seconds

• Total = total talk time
• Warning = Time before the end when the warning will compatible
• Seconds [optional] = When the numbers refer to seconds. If you leave this off, the numbers are in minutes.

If you get the following error:

ImportError: No module named 'blink1'

you probably installed the normal python setup.py install route. This doesn't install Blink1 properly.

If you get the following error:

ValueError: No backend available

you have the wrong version of PyUSB. The released version 1.0.0 has a bug in it. You need to use version 1.0.b1. To do that, do the following:

pip uninstall pyusb
pip install pyusb==1.0.b1

If you get the following:

usb.core.USBError: [Error 13] Access denied (insufficient permissions)

this is because you are using a Mac and libusb1 has a bug in it (since 2011). In the requirements I make sure you get pyusb. Unfortunately libusb1 gets installed by the blink1 library and it seems these are in conflict.

Just uninstall libusb1 and you should be fine:

pip uninstall libusb1