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New page: = Lab 3 - Switches, Logic, Loops = == Topics == * Learn about the variety of switch types: ** Push Button switches: Normally Open (NO) and Normally Closed (NC). ** Throw Switches: incl. SP...
= Lab 3 - Switches, Logic, Loops =
== Topics ==
* Learn about the variety of switch types:
** Push Button switches: Normally Open (NO) and Normally Closed (NC).
** Throw Switches: incl. SPST, SPDT, DPST, DPDT
* Boolean Logic: True, False, AND, OR, NOT, NAND.
* Relays.
* A Latch: one bit of information. [http://en.wikipedia.org/wiki/Latch_%28electronics%29#Simple_set-reset_latches Simple Set/Reset latch]
== Supplies ==
* 1 SPST Normally Open (N.O.) switch
* 1 SPST Normally Closed (N.C.) switch
* 5V, 40mA relay PB370-ND [http://relays.tycoelectronics.com/datasheets/T77_DS.pdf]
* 1 light bulb.
* Red and black hookup wire.
* Wire strippers, clippers, and pliers.
* Ridiculous Knife Switches (DPDT, available in class).
== Activities ==
* Using the continuity setting on your multimeter, determine which is your Normally Open (N.O.) and which is your Normally Closed (N.C.) pushbutton switch. Building a simple switch and light bulb circuit, test out how each one behaves:
[[Image:SPST_circuit.png | 300px]]
* With the ridiculous knife switches available in class, build a simple "selector switch" that turns on one of two bulbs:
[[Image:SPDT_bulbs.png | 300px]]
* Build an AND gate and verify its behavior (by filling in the truth table):
[[Image:AND_circuit.png | 300px]]
* Build an OR gate and verify its behavior:
[[Image:OR_circuit.png | 300px]]
* Familiarize yourself with the 5V relay.
** Which pins go to the coil?
** Which pins are the contacts that get switched?
** Is the relay Normally Open(NO) or Normally Closed (NC)?
** Using the multimeter for current sensing, how much current does the relay coil draw?
* With the relay, build a simple S-R latch:
[[Image:One_bit_memory.png | 300px]]
* Now, turn the latch into a pixel:
[[Image:One_pixel.png | 300px]]
* Congratulations You have built yourself one bit of digital memory and simple digital display!
* Now, returning to the idea of logic, label one side of a knife switch "TRUE" and the other side "FALSE".
* Working in small groups, use multiple knife switches (say five or more) and build a circuit that responds to a complex input. For instance, my circuit has five switches ("A" through "E") and one Light Bulb ("O"). The lighbulb, O, only turns on if switches A, C, and D are True, and switches B and E are false.
** Build your circuit and show that it works.
** Represent that circuit as a logical statement. O = (A + C + D) + (!B + !E)
** Draw that circuit as a diagram.
== Topics ==
* Learn about the variety of switch types:
** Push Button switches: Normally Open (NO) and Normally Closed (NC).
** Throw Switches: incl. SPST, SPDT, DPST, DPDT
* Boolean Logic: True, False, AND, OR, NOT, NAND.
* Relays.
* A Latch: one bit of information. [http://en.wikipedia.org/wiki/Latch_%28electronics%29#Simple_set-reset_latches Simple Set/Reset latch]
== Supplies ==
* 1 SPST Normally Open (N.O.) switch
* 1 SPST Normally Closed (N.C.) switch
* 5V, 40mA relay PB370-ND [http://relays.tycoelectronics.com/datasheets/T77_DS.pdf]
* 1 light bulb.
* Red and black hookup wire.
* Wire strippers, clippers, and pliers.
* Ridiculous Knife Switches (DPDT, available in class).
== Activities ==
* Using the continuity setting on your multimeter, determine which is your Normally Open (N.O.) and which is your Normally Closed (N.C.) pushbutton switch. Building a simple switch and light bulb circuit, test out how each one behaves:
[[Image:SPST_circuit.png | 300px]]
* With the ridiculous knife switches available in class, build a simple "selector switch" that turns on one of two bulbs:
[[Image:SPDT_bulbs.png | 300px]]
* Build an AND gate and verify its behavior (by filling in the truth table):
[[Image:AND_circuit.png | 300px]]
* Build an OR gate and verify its behavior:
[[Image:OR_circuit.png | 300px]]
* Familiarize yourself with the 5V relay.
** Which pins go to the coil?
** Which pins are the contacts that get switched?
** Is the relay Normally Open(NO) or Normally Closed (NC)?
** Using the multimeter for current sensing, how much current does the relay coil draw?
* With the relay, build a simple S-R latch:
[[Image:One_bit_memory.png | 300px]]
* Now, turn the latch into a pixel:
[[Image:One_pixel.png | 300px]]
* Congratulations You have built yourself one bit of digital memory and simple digital display!
* Now, returning to the idea of logic, label one side of a knife switch "TRUE" and the other side "FALSE".
* Working in small groups, use multiple knife switches (say five or more) and build a circuit that responds to a complex input. For instance, my circuit has five switches ("A" through "E") and one Light Bulb ("O"). The lighbulb, O, only turns on if switches A, C, and D are True, and switches B and E are false.
** Build your circuit and show that it works.
** Represent that circuit as a logical statement. O = (A + C + D) + (!B + !E)
** Draw that circuit as a diagram.