Jan 23 Class Notes

Open Circuit vs Short Circuit

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Some Stores:

• Forraker - have to know what you want
• HobbbytownUSA - motors
• HarborFreight - tools, smalle electronics, wire strippers 18-24 gauge

(Our wires, 22 gauge)

Deadlines for the Midterm

• Wednesday 1/25 > sketches for Midterm
• Wed. March 8 > presentation
• Project updates and documentation in blog
• How I got from point A to point B and everythign in between including failures.
• See the logic behind choices.
• START EARLY. Do NOT be afraid to restart.

Useful website: Draw.io (but probably easier to just draw circuit by hand)

Storing Data

bit: 1 or 0

8 bits = 1 byte

Range of a byte (0-255), so 256 possible choices including zero. Binary can be all zeros or all ones.

binary base 2 decimal base 10 (Insert Image/ Table for Binary vs Decimal)

Data Types

bool - true or false byte - unsigned (0 - 255) char - signed byte (-127 - 127) word - (0 - ~64k) int - signed word (~ -32k - ~32k) unsigned long - (0 - 4 mil) float - (decimal place) unsigned means: no +/-

rolling over: ex) byte > more than 255

4 bits - nibble 8 bits - byte 16 bits - word 32 bits - long 32 bits - float (decimal place) 64 bits - double long avoid floating point math if we can, hardware doesn’t do division

data type name value ex) byte sensorValue =0;

Variables

void setup() { }

Some functions need parameters. Parenthesis signal a function. No parenthesis signal a variable. Can’t write code without variables. Have to define functions and variables BEFORE using them.

rnd = random() gives us a random, # and stores it in rnd void: function isn’t returning anything. map: scales one range to another.

Conditional

(insert image of conditional function)

Blink Without Delay

unsigned long timestamp = 0; two equal signs > compare

int LEDState = LOW; const long interval = 1000

void setup() { } pinMode(LEDBUILTIN, OUTPUT);

unsignedlongcurrentimestamp= millis();

if currenttimstamp - previoustimestamp > = () { }

if (LEDState == LOW) {

} (LEDState = HIGH); } else {LEDState = LOW;

} previoustimestamp = currenttimestamp

digitalwrite (LEDBUILTIN, LEDState)