Simplest Attiny85 based watch

We are used to see different kinds of DIY watches. Some of them try to stuff lots of functionality, other make fancy time telling format or simply mimic smart watches. But why not build a watch that only tells time in a simple manner. This Attiny85 watch is what it does. Schematic is very simple and straight forward – Attiny85 microcontroller, 12 LEDs, push button, three resistors and coin cell battery. Such simplicity allows building small watch shaped PCB where all components are fit to look nice and light. Since microcontroller comes with only 5 I/O pins (excluding reset), LEDs are connected using smart Charlieplexing method that allows saving pins for simple I/O tasks. The only shortcoming of this watch that time is counted using microcontrollers internal clock which may … Continue reading

Attiny10 miniature breakout board

If you want your microcontroller to fit in tight spaces you need to use very small packages. One optin is to choose Atmel Attiny10 microcontroller which is really tiny. It has 6 pins, where 4 of them are I/O. It features 1KB of Flash, 32B of RAM and can be clocked at 12MHz. Power supply can vary between 1.8V to 5.5V. They come in two types of packages – SOT-23 and UDFN. Dan Watson have built a mini breakout board for Attiny10 mincrocontroller. He wanted it to be really small and came out with size similar to 5mm LED head. To reduce size, he used small pitch (0.05”) header pins that doesn’t fit to breadboard. So additionally he made a special adapter board to be able to program it with … Continue reading

Placing watch on the ring

Building a wrist watch is quite a challenge, but when we want to squeeze electronics in to ring then real fun begins. It becomes even harder when using building blocks that are meant for prototyping. Anyway take a look at following instructable, where 陳亮 have put decent looking ring watch. He had to squeeze Attiny85 microcontroller which comes in SOIC package. It’s been soldered on small prototyping PCB. Another large part of it is display. It’s 64×32 OLED display module with SSD1306 controller on board. Display is a biggest part of all and determines the ring width. Ring watch also carries s CR1220 battery with expectancy to last at least for half an year. Three push buttons gives ability to change settings. Time is counted internally and here helps Paul … Continue reading

Universal electronics component tester

When you are working with electronics or simply building stuff, you probably always end up testing one or several components for their faults or making sure parameters are within specs. Most of those tasks can be done with multimeter. Obviously any multimeter have resistor and capacitance testing modes. Anyway, there are more components that may be tested and using multimeter might require some setup. Baweja_akshay have built pretty universal component tester which is capable of testing most of non power electronics components. I is capable of testing resistors, capacitors including ESR, BJTs, FETs, MOSFETs, JFETs, Thyristors (SCR, DIAC, TRIAC), IGBTs, diodes. Additionally tester is capable of measuring voltages up to 50V, frequency and even generate signals. Optionally there is an IR code detector. The tester is based on Atmega328 microcontroller … Continue reading

Wearable OLED display powered with attiny85

Wearable electronics is commonly used in many areas. We are not talking about professional stuff like medical devices, but more hobby corner. But who knows where is a limit. Today anyone can assemble wearable projects with cheap building blocks that are mostly based on Arduino. AwesomePCB have shared his instructable on how to build a wearable OLED display covered with leather frame that blends pretty well on fabric. He used small SSD1306 128×64 OLED display which is connected to small Attiny85 Arduino compatible board. Coin cell battery is enough to power it for quite some time. He paid some attention to details on how display is attached to leather piece and how this piece is snapped to clothes. You can do many fun stuff with the display including a temperature … Continue reading