Category Archives: c-tinys

ATTiny and Teensy MCUs

DTMF Detector / Decoder Circuit

Note1: The FCC frowns upon you connecting devices to the telephone system (the old copper line network a.k.a. POTS). In my testing, this device is connected to a small PBX. When I’m done it will be connected to a VoIP … Continue reading

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Resetting / Rebooting ATTiny85 with Watchdog Timer (WDT)

I was expecting this to be a no-brainer. I use WDT on Arduinos w/o any trouble. The code for Arduino would roughly be: #include <arv/wdt.h> … wdt_enable(WDTO_1s); while (true) {} After one second, the arduino reboots because of the WDT. … Continue reading

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Can’t Get I2C to Work on an Arduino Nano? (Pinout Diagrams)

Maybe it is because many of the pinout diagrams for the Nano have SCL and SDA on the wrong pins. You probably think (as I did and as the guys laying out the pinout diagrams) that these would be on … Continue reading

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Using the Teensy 3.1 Real Time Clock (RTC)

One of my interests in the Teensy is the built-in RTC. Especially since the RTC module I was using last summer with an arduino ended up loosing time pretty quick (as I recall it would loose an hour a week). … Continue reading

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Wiring Teensy 3.1 and ENC28J60 Ethernet Module Together

The teensy is pretty cool, but with all that processing power, it needs to be able to do more than turn pins on and off to communicate. If I’m going to use this for anything truly useful, I’ll want it … Continue reading

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Teensy 3.1 – Emulating a USB Keyboard

My primary motivation for purchasing a Teensy is to emulate a keyboard to set up a little practical joke for someone. So I need to get the Teensy running in a manner in which if I press a button, it … Continue reading

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Teensy 3.1 First Look – Features, Installation, and Compiling Blink

I purchased a Teensy 3.1 several months ago and finally got around to having a look at it. The Teensy is made by PJRC and full details can be found at I purchased mine from Sparkfun. These notes apply … Continue reading

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Low Power ATTiny85 Experiment

I spent time on and off this summer trying to build a micro-controller-based circuit that would run on minimal power. My desire is to build a circuit that runs on solar power but will fall back to battery during the … Continue reading

Posted in c-tinys, Low Power Arduino | 6 Comments

ATTiny85 Wake from Sleep on Pin State Change Code Example

I spent an inordinate amount of time trying to figure out how put my ATTiny85 to sleep and then wake it up when the state of a pin changes. So I’ll document my test code in case anyone else goes … Continue reading

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Programming ATTiny85 Using Sparkfun Tiny AVR Programmer

Today I want to program an ATTiny85 for the first time. Just getting the blinky program to run is a good start. The ATTiny85 is an 8 pin ATMEL microcontroller. 6 pins can be used for I/O and they are … Continue reading

Posted in c-tinys | Tagged | 9 Comments