Category Archives: c-arduino

Arduino Posts

Making a Data Only Cable For Teensy/Arduino/Nano

Been working on a complicated teensy project that is going to the other side of the state for testing. So I’ve been building a testing platform that consists of a Raspberry Pi connected to the Teensy via USB. I can … Continue reading

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Remote Monitoring and Upgrading of Arduino/Teensy via Networked Raspberry Pi

This post covers how to remotely monitor / upgrade an Arduino or other MCU behind a firewall. (Jump down to the Dec 2016 Update for Notes about the Duplicity Service that will easily and quickly allow remote access to an … Continue reading

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Using Modulus Arithmetic to Navigate a Circular List

I have to go thru my notes every so often to find the formula for navigating backwards, so I’ll post this stuff here in case anyone else finds it useful. Modulus math is very handy for dealing with circular functions … Continue reading

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Writing Code to Handle Arduino’s millis() Roll Over

The Arduino’s millis() function returns the number of milliseconds since the arduino started running. It returns an unsigned long, 32 bit, value. A 32 bit unsigned word can contain 0 – 4,294,967,285 (2^32-1). When millis() gets to 4,294,967,285 milliseconds and … Continue reading

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Adafruit Thermal Printer Library haspaper() Function Fix

I posted this ‘fix’ on Adafruits’ forum as well. I have been playing with their mini Thermal Printer ( I started testing the haspaper function in their thermal printer library which returns true if there is paper else false. In … Continue reading

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ESP8266/Arduino IDE: Communicating with TCP

Today’s goal is to transmit and receive TCP packets with my ESP-01, building on yesterday’s post, ESP8266/Arduino IDE: Connecting to a Network with WIFI. To make this process a little easier, I will be communicating with an Echo server so … Continue reading

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Sniffing *ALL* Arduino Network Packets

For this post, I’m going to assume you are already somewhat familiar with WireShark/tcpdump for monitoring network traffic. Wireshark is great for viewing packets, but it only sees the traffic coming to/from the system that is running it. Generally, that … Continue reading

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Switch Debouncing and Waiting for a Button Press

For the several years I’ve been working with arduinos I have went thru quite a few variations of switch debouncing. Some I’ve found on line, some I’ve written myself. Most of the ones I’ve found online I felt were kind … Continue reading

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Connecting NHD-C0220BiZ-FSW-FBW-3V3M I2C LCD Display to a Teensy

Been working on a Teensy project that needs an I2C LCD display. All I had in my junk bins were 5V displays that I’ve been using on Arduinos. I got a temporary solution running by using a level shifter to … Continue reading

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Cheap Battery Backup for Raspberry Pi or Arduino

I’ll throw this out real quick as I’m sure others are trying to do the same thing. Been working on a RPI project that is ‘mission critical’. It cannot fail because it looses power and the file system corrupts. So … Continue reading

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