Components you can use

• Bujeon BBM-01 Buzzer
  
  This little guy has a screaming loud sound when you drive it at 2700 Hz. It's quiter for other frequencies. Driven directly by the pic, it's quite audible.
  
  Frequency Response of BBM-01

  Here is some sample code to make a 2700 Hz tone.
  Here is the full data sheet.
  All Electronics stocks these guys as item PZB-01, three for $1.00.

• Semitec #103AT-2 Thermistor
  

  Part No.	Rated zero-power resistance R25	B Value B25/85	Operating temperature range
  103AT-2	10.0k ohm	3435	-50~110

  Here is the analog hack code we saw in lecture two to read the resistance with a digital port.
  Here is the full data sheet.
  All Electronics part number THR-20, price two for a dollar.

• Mystery Thermistor

  The thermistors with leads already on them are not the ones we ordered. Investigate their resistance with a volatge meter to find out what they do. Feel free to chop off the leads.

• Photo Resistors

  The magic of cadmium sulfide is that the resistance changes in response to the amount of light. We have little ones (allcorp part PRE-14) and big hermetically sealed ones (allcorp part PRE-16). Both range in resistance from 35 Ohms in the dark to 500 kOhms in light.

• Potentiometers
  

  Potentiometers are variable resistors that you can twist or slide. We've got a good variey of them.

• Relays

  Relays are switches that microprocessors can control. They're essential for controlling high-power, like turning on a desk lamp with the PIC.

  We have a handful of solid state relays -- which are extra cool because they have no moving parts. Since they use little power the PIC output can drive them directly. To use mechanical relays with the PIC you'll need a little amplifier circuit.

  

  "This Solid State Relay has a max Load Current rating of 25A, and a max peak single cycle surge current rating of 250A. Operating voltage 90-280VAC,  47-63Hz. Random Turn-On, phase controllable (DC control)."
  --KRISTRONIC.com

  Here is the data sheet for the Crydom Series I D2425-10 Solid State Relay.

• Switches

  There are lots and lots of different switches and you can never find the one that's just right.

  We've got toggle switches, momentary push-button switches, push-on/push-off switches, and DIP switches. We've got single-pole and dual-pole, single-throw and dual-throw. We've got micro, mini, and standard sizes. But in the circuit it's all the same: wire the input pin on the pic to the switch and to 5V by a pull-up resistor. Wire the other side of the switch to ground.

  picture

  To make life even easier, the pins on port b have internal pullup resistors, which you can enable with the command:

  port_b_pullups(TRUE);

  We also have some special switches. Tilt Switches which close when they are tilted, reed switches which close when they are near a magnet, and encoders, which set a number of switches to correspond to a numerical selection or rotational position.

• Breakbeam sensor

  This little devil has a IR led and an IR receiver neatly packaged in a little U. If anything enters the U and obstructs the path of the IR, the PIC can tell.

• Other stuff that we have, but haven't had time to play with yet
  • Bar Graph LED
  • 7 Segment LED
  • 16x2 character LCD display
  • Motorized dual-potentiometer
  • IR reflectance sensor
  • Surface mount Hall Effect sensors
  • Electrovoltaic photocell (should be enough to power the PIC)
  If you want to try your hand of any of these components, let the TAs know. If you figure it out, we'll put it on the web so everyone can use it.