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Tanner Collin 2022-04-09 18:40:28 -06:00
commit ef48107c81
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125
bluetooth/bluetooth.ino Normal file
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#include <bluefruit.h>
#include <Adafruit_LittleFS.h>
#include <InternalFileSystem.h>
#include "HX711.h"
//#define calibration_factor -6980.0 // black wired load cell
#define calibration_factor -5760.0 // orange wired load cell
#define DOUT 30
#define CLK 27
HX711 scale;
// BLE Service
BLEDfu bledfu; // OTA DFU service
BLEDis bledis; // device information
BLEUart bleuart; // uart over ble
BLEBas blebas; // battery
void setup()
{
Serial.begin(115200);
scale.begin(DOUT, CLK);
digitalWrite(CLK, LOW); // hangs without this
scale.set_scale(calibration_factor); //This value is obtained by using the SparkFun_HX711_Calibration sketch
scale.tare(); //Assuming there is no weight on the scale at start up, reset the scale to 0
Serial.println("");
Serial.println("");
Serial.println("Load Cell Demo");
Serial.println("--------------\n");
Bluefruit.autoConnLed(true);
Bluefruit.configPrphBandwidth(BANDWIDTH_MAX);
Bluefruit.begin();
Bluefruit.setTxPower(4);
Bluefruit.Periph.setConnectCallback(connect_callback);
Bluefruit.Periph.setDisconnectCallback(disconnect_callback);
bledfu.begin();
bledis.setManufacturer("Odai");
bledis.setModel("TUT Load Cell");
bledis.begin();
bleuart.begin();
blebas.begin();
blebas.write(100);
startAdv();
Serial.println("Please use Adafruit's Bluefruit LE app to connect in UART mode");
}
void startAdv(void)
{
// Advertising packet
Bluefruit.Advertising.addFlags(BLE_GAP_ADV_FLAGS_LE_ONLY_GENERAL_DISC_MODE);
Bluefruit.Advertising.addTxPower();
// Include bleuart 128-bit uuid
Bluefruit.Advertising.addService(bleuart);
// Secondary Scan Response packet (optional)
// Since there is no room for 'Name' in Advertising packet
Bluefruit.ScanResponse.addName();
/* Start Advertising
* - Enable auto advertising if disconnected
* - Interval: fast mode = 20 ms, slow mode = 152.5 ms
* - Timeout for fast mode is 30 seconds
* - Start(timeout) with timeout = 0 will advertise forever (until connected)
*
* For recommended advertising interval
* https://developer.apple.com/library/content/qa/qa1931/_index.html
*/
Bluefruit.Advertising.restartOnDisconnect(true);
Bluefruit.Advertising.setInterval(32, 244); // in unit of 0.625 ms
Bluefruit.Advertising.setFastTimeout(30); // number of seconds in fast mode
Bluefruit.Advertising.start(0); // 0 = Don't stop advertising after n seconds
}
void loop()
{
char buf[100] = "";
int reading = (int) scale.get_units();
String message = String(reading) + "\n";
message.toCharArray(buf, message.length()+1);
bleuart.write(buf, message.length()+1);
delay(50);
}
// callback invoked when central connects
void connect_callback(uint16_t conn_handle)
{
// Get the reference to current connection
BLEConnection* connection = Bluefruit.Connection(conn_handle);
char central_name[32] = { 0 };
connection->getPeerName(central_name, sizeof(central_name));
Serial.print("Connected to ");
Serial.println(central_name);
}
/**
* Callback invoked when a connection is dropped
* @param conn_handle connection where this event happens
* @param reason is a BLE_HCI_STATUS_CODE which can be found in ble_hci.h
*/
void disconnect_callback(uint16_t conn_handle, uint8_t reason)
{
(void) conn_handle;
(void) reason;
Serial.println();
Serial.print("Disconnected, reason = 0x");
Serial.println(reason, HEX);
}

80
calibrate/calibrate.ino Normal file
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/*
Example using the SparkFun HX711 breakout board with a scale
By: Nathan Seidle
SparkFun Electronics
Date: November 19th, 2014
License: This code is public domain but you buy me a beer if you use this and we meet someday (Beerware license).
This is the calibration sketch. Use it to determine the calibration_factor that the main example uses. It also
outputs the zero_factor useful for projects that have a permanent mass on the scale in between power cycles.
Setup your scale and start the sketch WITHOUT a weight on the scale
Once readings are displayed place the weight on the scale
Press +/- or a/z to adjust the calibration_factor until the output readings match the known weight
Use this calibration_factor on the example sketch
This example assumes pounds (lbs). If you prefer kilograms, change the Serial.print(" lbs"); line to kg. The
calibration factor will be significantly different but it will be linearly related to lbs (1 lbs = 0.453592 kg).
Your calibration factor may be very positive or very negative. It all depends on the setup of your scale system
and the direction the sensors deflect from zero state
This example code uses bogde's excellent library: https://github.com/bogde/HX711
bogde's library is released under a GNU GENERAL PUBLIC LICENSE
Arduino pin 2 -> HX711 CLK
3 -> DOUT
5V -> VCC
GND -> GND
Most any pin on the Arduino Uno will be compatible with DOUT/CLK.
The HX711 board can be powered from 2.7V to 5V so the Arduino 5V power should be fine.
*/
#include "HX711.h"
#define DOUT 30
#define CLK 27
HX711 scale;
float calibration_factor = -7050; //-7050 worked for my 440lb max scale setup
void setup() {
Serial.begin(115200);
Serial.println("HX711 calibration sketch");
Serial.println("Remove all weight from scale");
Serial.println("After readings begin, place known weight on scale");
Serial.println("Press + or a to increase calibration factor");
Serial.println("Press - or z to decrease calibration factor");
scale.begin(DOUT, CLK);
digitalWrite(CLK, LOW); // hangs without this
scale.set_scale();
scale.tare(); //Reset the scale to 0
long zero_factor = scale.read_average(); //Get a baseline reading
Serial.print("Zero factor: "); //This can be used to remove the need to tare the scale. Useful in permanent scale projects.
Serial.println(zero_factor);
}
void loop() {
scale.set_scale(calibration_factor); //Adjust to this calibration factor
Serial.print("Reading: ");
Serial.print(scale.get_units(), 1);
Serial.print(" lbs"); //Change this to kg and re-adjust the calibration factor if you follow SI units like a sane person
Serial.print(" calibration_factor: ");
Serial.print(calibration_factor);
Serial.println();
if(Serial.available())
{
char temp = Serial.read();
if(temp == '+' || temp == 'a')
calibration_factor += 10;
else if(temp == '-' || temp == 'z')
calibration_factor -= 10;
}
}

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measure/measure.ino Normal file
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/*
Example using the SparkFun HX711 breakout board with a scale
By: Nathan Seidle
SparkFun Electronics
Date: November 19th, 2014
License: This code is public domain but you buy me a beer if you use this and we meet someday (Beerware license).
This example demonstrates basic scale output. See the calibration sketch to get the calibration_factor for your
specific load cell setup.
This example code uses bogde's excellent library: https://github.com/bogde/HX711
bogde's library is released under a GNU GENERAL PUBLIC LICENSE
The HX711 does one thing well: read load cells. The breakout board is compatible with any wheat-stone bridge
based load cell which should allow a user to measure everything from a few grams to tens of tons.
Arduino pin 2 -> HX711 CLK
3 -> DAT
5V -> VCC
GND -> GND
The HX711 board can be powered from 2.7V to 5V so the Arduino 5V power should be fine.
*/
#include "HX711.h"
#define calibration_factor -10160.0 //This value is obtained using the SparkFun_HX711_Calibration sketch
#define DOUT 3
#define CLK 2
HX711 scale;
void setup() {
Serial.begin(9600);
Serial.println("HX711 scale demo");
scale.begin(DOUT, CLK);
scale.set_scale(calibration_factor); //This value is obtained by using the SparkFun_HX711_Calibration sketch
scale.tare(); //Assuming there is no weight on the scale at start up, reset the scale to 0
Serial.println("Readings:");
}
void loop() {
//Serial.print("Reading: ");
//Serial.print(scale.get_units(), 1); //scale.get_units() returns a float
//Serial.print(" lbs"); //You can change this to kg but you'll need to refactor the calibration_factor
//Serial.println();
Serial.println(scale.get_units(), 1);
}