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--- haas:fall2020:common:projects:led1 [2021/09/05 09:49] – [Program] wedge
+++ haas:fall2020:common:projects:led1 [2021/09/05 09:58] – [On your pi] wedge
@@ Line 223: / Line 223: @@
 1 0 1
 1 1 0
-1 1 1   <-- 15
+1 1 1   <-- 15, the maximum value to display
 0 0 0   <-- 0, we "roll over" and start again
 0 0 1
@@ Line 232: / Line 232: @@
 The program files provided for this project are, while not complete, a good base to start from. Be sure to ASK QUESTIONS, and do so EARLY enough so that you aren't in a mad dash to make the deadline.
+=====Bitwise logic=====
+Since the off/on state of each LED is essentially binary in nature (or one bit of an overall sequence), why not utilize the powerful bitwise tools available to us in C?
+====bitwise-AND====
+C provides a bitwise AND operator, the **<nowiki>&</nowiki>** symbol, which can be used in equations to perform bitwise-AND operations:
+<code c>
+char value  = 5;         // 00000101 in binary
+value       = value & 6; //   00000101
+                         // & 00000110
+                         //   ========
+                         //   00000100
+</code>
+Remember the truth table for the AND:
+<code>
+( AND )
+A B | X
+====+===
+F F | F
+F T | F
+T F | F
+T T | T
+</code>
+Think of how this property could be used in combination with other concepts we've learned about in C to solve the problem at hand.
+====bitwise-iOR====
+C provides a bitwise inclusive OR operator, the **<nowiki>|</nowiki>** symbol, which can be used in equations to perform bitwise-iOR operations:
+<code c>
+char value  = 5;         // 00000101 in binary
+value       = value | 6; //   00000101
+                         // & 00000110
+                         //   ========
+                         //   00000111
+</code>
+Remember the truth table for the iOR:
+<code>
+( iOR )
+A B | X
+====+===
+F F | F
+F T | T
+T F | T
+T T | T
+</code>
+Think of how this property could be used in combination with other concepts we've learned about in C to solve the problem at hand.
+====bitwise-xOR====
+C provides a bitwise exclusive OR operator, the **<nowiki>^</nowiki>** symbol, which can be used in equations to perform bitwise-xOR operations:
+<code c>
+char value  = 5;         // 00000101 in binary
+value       = value ^ 6; //   00000101
+                         // & 00000110
+                         //   ========
+                         //   00000011
+</code>
+Remember the truth table for the xOR:
+<code>
+( xOR )
+A B | X
+====+===
+F F | F
+F T | T
+T F | T
+T T | F
+</code>
+Think of how this property could be used in combination with other concepts we've learned about in C to solve the problem at hand.
 ====Grabbing project resources (on lab46)====
 I have prepared a **grabit** for resources related to this project. To obtain:
@@ Line 256: / Line 333: @@
 ====On your pi====
-Study and run this program on your pi in conjunction with testing and verifying operation of your properly hooked up electronics circuit. When done, submit it on lab46.
+Implement the needed program on your pi in conjunction with testing and verifying operation of your properly hooked-up electronics circuit. When done, submit it on lab46.
 To utilize the needed functionality for this project, you will need to ensure you have the following packages installed: