MAS.S60
Problem Set #6
Due Friday 10.12.12


This problem set can either be done individually or with your final project group.
 I.E., a single group can get 1 setup working, and have it count for both people.


Problem 1:  Connect up your CDS photocell to your arduino's analog in, and have the
 onboard LED go on/off for some arbitrary light level in the middle of the sensor's
 range.  This way you can toggle the light on/off by covering the photocell with your
 hand.

Problem 2:  Now connect up the IR reciever to the arduino's UART RX in, and the IR
 transmitter to another pin.  Send the photocell value over the IR link in serial,
 and have it turn the onboard LED on/off as before.  The datasheet for the IR
 reciever is difficult to come by, so it is included here:

http://www.sharpsme.com/download/GP1UX51QS-SS2pdf

 and a simple pinout is given here:

http://web.media.mit.edu/~geppetto/vids/irrx.jpg

The IR reciever needs 38kHz modulation, with pulse widths of at least 200us.  So i
 would reccomend a very slow baud rate of around 1kbps.  Since the IR transmitter
 needs to be modulated, a simple way of doing this is using the Tone() library to
 generate a frequency, and then turn it on and off. examples of how to do this are given here:

http://web.media.mit.edu/~geppetto/vids/irmod.jpg

Final Project:  The last few problem sets have been working towards a final project,
 which will be due in class on Wednesday, 10.17.12.  If you are doing an alternate
 project, please show that in class.  otherwise, this is what the final project should
 include:

A functioning cassette player, which varies its playback tone based upon the light
 level at the CDS photocell.  The photocell value should be sent wirelessly, over the
 IR link (as above), and the audio output should be on the speaker taken from the
 mystery PCB.  A simple amplifier for the speaker should be used, to make it a bit
 louder than it would be otherwise.  If you want to make it do something else, feel
 free to add/substitute things.