Arduino Archives - MicroController Electronics

Jan 13 2021

STM32F103C8T6 Pin Tester to check your soldering

By earl in Informational, STM32F103C8T6

How good are you at soldering? Here is the STM32F103C8T6 microcontroller board that I use and have to solder all of the pins. Sometimes when I solder pins to the board, the connection looks OK and even tests OK with continuity on a multimeter. However, the solder connections even though they pass those two …

Dec 30 2020

5 Way Navigation Button connected to an Arduino or STM32F103C8T6

By earl in Informational

A 5 way navigation button actually has 7 different navigational settings. It has a lot of functionality in a small package. The ‘button’ on it can be moved/pushed in 4 directions ( labeled up, down, left, right) or pressed down. There are also two other switched buttons labeled ‘Set’ and ‘Reset’ for a total of …

Jan 27 2018

How to keep an ENC28J60 Module from Freezing

By earl in Informational

The ENC28J60 module is good for attaching an Arduino to a LAN or the Internet. The one real problem in doing so is how to keep an ENC28J60 module from freezing. No, not temperature wise ! 🙄 (‘Freezing’ in the sense of locking up, stop working, etc.) There are many Ethernet arduino libraries for the …

Jan 25 2018

Switching 12V from a 5V Arduino

By earl in Informational

I built a circuit to allow switching 12V from a 5V Arduino. Here is the wiring diagram and a picture of the actual circuit: Get the Fritzing source HERE. The side with two connections attaches to the 12V device being switched ON/OFF. The side with three connectors, connects to the 12V …

May 13 2016

I2C Wire Chat Between Two Arduinos

By earl in Arduino, Informational

Someone asked me the other day if it was possible to have a ‘chat’ between Arduinos using the I2C Wire library. I came up with ‘proof of concept’ code called ‘I2C Wire Chat Between Two Arduinos’. Here is the sketch: I2C Wire Chat Between Two Arduinos

/* 
 
 I2C wire chat
 From: earl@microcontrollerelectronics.com

 Analog Pin 5 SCL
 Analog Pin 4 SDA
 Common ground

*/

#include <Wire.h>
#define WireDevice 8

String buffer;
int mode;

void setup() { Serial.begin(9600); }

void loop() {
  while (Serial.available()) {
    char c = Serial.read();
    if (c != '\n') {
      if (c == '\r') continue;
      buffer += c;
      continue;
    }
    else {  
      buffer += '\0';
      if (buffer[0] == '#') {
        if (buffer[1] == 'm') {
          if (mode != 'm') {
            mode = 'm';
            master();
            Serial.println("Master mode");
          }
        }
        if (buffer[1] == 's') {
          if (mode != 's') {
            mode = 's';
            slave();
            Serial.println("Slave mode");
          }
        }
        buffer = "";
        continue;
      }
      if (mode == 'm') {
        Wire.beginTransmission(WireDevice); 
        int i = 0;
        while (buffer[i]) { Wire.write(buffer[i]); i +=1; }
        Wire.endTransmission();    
      }
      else Serial.println("Invalid Mode");
      buffer = "";
    } 
  }
}

void master() {
  Wire.begin();
  Serial.println("Master Initialized");
}

void slave() {
  Wire.begin(8);                
  Wire.onReceive(receiveEvent);
  Serial.println("Slave Initialized");
}

void receiveEvent(int howMany) {
  while (1 < Wire.available()) {
    char c = Wire.read();
    Serial.print(c);     
  }
  char c = Wire.read();
  Serial.println(c);     
}

I2C wire chat

From: earl@microcontrollerelectronics.com

Analog Pin 5 SCL

Analog Pin 4 SDA

Common ground

#include <Wire.h>

#define WireDevice 8

String buffer;

int mode;

void setup() { Serial.begin(9600); }

void loop() {

while (Serial.available()) {

char c = Serial.read();

if (c != '\n') {

if (c == '\r') continue;

buffer += c;

continue;

}

else {

buffer += '\0';

if (buffer[0] == '#') {

if (buffer[1] == 'm') {

if (mode != 'm') {

mode = 'm';

master();

Serial.println("Master mode");

}

if (buffer[1] == 's') {

if (mode != 's') {

mode = 's';

slave();

Serial.println("Slave mode");

}

buffer = "";

continue;

}

if (mode == 'm') {

Wire.beginTransmission(WireDevice);

int i = 0;

while (buffer[i]) { Wire.write(buffer[i]); i +=1; }

Wire.endTransmission();

}

else Serial.println("Invalid Mode");

buffer = "";

}

void master() {

Wire.begin();

Serial.println("Master Initialized");

}

void slave() {

Wire.begin(8);

Wire.onReceive(receiveEvent);

Serial.println("Slave Initialized");

}

void receiveEvent(int howMany) {

while (1 < Wire.available()) {

char c = Wire.read();

Serial.print(c);

}

char c = Wire.read();

Serial.println(c);

}

Setup two Arduinos connected by a length of …

Arduino, I2C, Wire
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Aug 31 2015

A Python script to run the Arduino MiniPirate Sketch

By earl in Arduino, Informational

A while back I wrote about the BusPirate. You can view that post here. In it, I mention an Arduino sketch called the “MiniPirate” which allows you to try some of the functions of the BusPirate on an Arduino. Over time, I have found that sketch to be very useful. You can use it to …

Jul 06 2015

Arduino Leonardo and SPI Communications

By earl in Arduino, Informational

I just found out that my favorite Arduino of choice (the Leonardo) has a problem with SPI “Serial Peripheral Interface” communications (if you need to use the SS pin). For SPI (which is bidirectional) , the following pins are normally used: SS – Slave Select – digital 10. You can use other digital pins, but …

Arduino, ENC28J60, SPI
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Aug 09 2014

Wireless Bluetooth Module for your Arduino

By earl in Modules

If you’d like to wirelessly attach your Arduino to another device (such as a phone or tablet) via bluetooth, I’d recommend the serial bluetooth module from Elecrow.com. Here is what they look like: The module has firmware from BOLUTEK. The PDF document with all of the available BOLUTEK commands is BLK-MD-BC04-B_AT COMMANDS . I …

Aug 07 2014

Connecting an Arduino to a LAN with the ENC28J60

By earl in Arduino, Modules

I picked up a couple of these modules: from Elecrow.com so I could attach (communicate with and control) several of my Arduinos through a LAN connection. The main chip is the ENC28J60 from microchip.com. These modules are better than an Ethernet Shield in that you can easily attach these to any Arduino and they …

Aug 04 2014

Atmel versus PIC Microcontrollers

By earl in Informational

Many years ago (I am old ;-)) I was asked which microcontrollers are best, ones from PIC (microchip.com) or ones from Atmel (atmel.com). At the time I was asked, there was a lot of discussion about chip architecture, instruction sets and which chip was best. I thought at the time and still feel this way, …

Arduino, Atmel, PIC
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Tag: Arduino