by Juan J. Martínez:
This is my first serious attempt to learn electronics. DAN64 is my first project and it has been a discovery process during 3 months of my free time. I had to learn a lot of things I didn’t know much about, from basic electronics to the details of the AVRs -and specifically the ATmega328-, and a whole world of things in between such as signalling, protocols, interfaces, modulation and demodulation, SDKs, EDA software, prototyping, PCB fabrication, etc.
I’m certain that in this project I’m doing many stupid things and I’m sure my approach to solving some of the problems is not the best, but in my discharge I can only say: it works! (to some extent at least).
I got lots of gotcha! moments, ups and downs where I though I couldn’t finish the project because perhaps what I was trying to achieve was just impossible.
So this is not about perfection but about good enough for me and about the learning process and having fun.
DAN64 – an AVR based 8-bit microcomputer – [Link]
The Zero Tiny BLE is a small low cost and low powered embeddable board with an AVR ATTiny85 microcontroller and a Bluetooth 4.0 (Bluetooth Low Energy or BLE) radio.
AVR ATTiny85 microcontroller running at 8MHz internal clock and 3.3V. ATTiny85 Datasheet.
HM-10 Bluetooth 4.0 Low Energy module. HM-10 Datasheet.
Powered by single cell 3.7V Lithium Polymer battery (LiPo) or USB B mini port.
LiPo battery recharge capabilities via the USB B mini port.
Standard UART communication over Bluetooth 4.0.
Easy prototyping via breadboard.
Use either Arduino or AVR-GCC development environments.
Small form factor of 20mm x 47mm (0.79” x 1.85”)
You can purchase a complete board at zeroengineering.io
You can order unpopulated boards from OSH Park
Zero Tiny BLE – low cost and low powered embeddable board – [Link]
by Radu Motisan @ pocketmagic.net:
For many of my previous projects I used AVR Microcontrollers extensively. I started with the Atmega8 and moved to superior AVR variants depending on the application complexity and requirements. Before designing any particular application, I usually do my research on a development board. It is a PCB featuring the target microcontroller and minimal support logic that usually covers a regulated power supply, pin headers to connect peripherals and/or a few LEDs used for basic debugging.
Such boards are available in many shapes and colours, from simple to complex and most of the times they are affordable (after all we’re talking about a minimal PCB with a microcontroller and a few, mostly passive, components).
DIY AVR Development Board with Atmega128 – [Link]
by Pieter @ piconomic.co.za:
If you can beg, steal or borrow an Atmel ISP programmer, then you can use the Arduino environment to develop on the Atmel AVR Atmega328P Scorpion Board. An Arduino on Scorpion Board guide, Optiboot bootloader and example sketches have been added.
If you own an Arduino Uno board, you can now try out the Piconomic FW Library risk free without abandoning the creature comforts of the Arduino environment. You can use the existing Optiboot bootloader to upload code. I have added a getting started guide for the Arduino Uno. There are examples, including a CLI (Command Line Interpreter) Application that creates a “Linux Shell”-like environment running on the Arduino Uno so that you can experiment with GPIO, ADC, I2C and SPI using only Terminal software (for example Tera Term)… it is really cool!
Piconomic FW Library 0.4.2 released – [Link]
Davide Gironi writes:
The PWM frequency have to be selected in the way that the switch frequency is much higher than the dynamics of the motor.
To avoid noise from the motor, the choosen PWM frequency is 20Khz. Which is a know to know frequency.
So, with this one, you can drive up to 4 motors independently controlling:
*slow start / stop
Setup parameters are contained in dcmotorpwm.h
This library was developed on Eclipse, built with avr-gcc on Atmega8 @ 8MHz.
Driving a DC motor using PWM with AVR ATmega – [Link]
An autonomous AVR ISP programming device with SD-Card, Nokia display, ZIF socket and standard 6-pin ISP interface:
From project to project the number of hex files on our PC was increasing. Many people send us their virgin ATMegas to get them flashed. And last not least distributing PCB’s and pre-flahed chips via agile-hardware forced us to burn many, many AVRs. In principle this is a work an ape should do but reality was different. So we spend munch time in this boring job. To much time …
Thus it was just consequent to think about a device that would do the job for us. Here is the result, the SolderLab Easy Auto Programmer V1.0. An All-in-one AVR programmer with SD-card, Nokia Display, a ZIF-Socket and a 6-pin ISP interface. With this device the programming of an AVR is done in seconds including the setting of fuse bits (before AND after flashing), flashing the chip, verifying the flash. And all this without any connection to the PC and by pressing just one single button. You just have to put all your hex files into a folder called “hex” on a standard FAT32 formatted SD card, put the card into the programmer an supply it with some voltage (7-20V). That’s it the rest is done by the “ape”.
Stand Alone AVR Programmer – [Link]
This minimalistic board is packed with features and comes with an extensive ecosystem of documentation and firmware.
For the student (we are never too old) that wants to fast track his career as a professional firmware developer there is:
- a detailed getting started guide
- an Atmel AVR quick start guide, with tutorials and examples
- Recommend best practices
For the developer that wants to improve his game there is:
- A header to quickly connect different kinds of peripherals (GPIO, A/D, UART, SPI & I2C). Notice that each interface has it’s own +3V3 and GND pins to make wiring easier and also improves EMC.
- A full-featured CLI application to experiment with the connected device and verify that it works, before committing to a single line of C code.
- A firmware framework that lays the foundation so that you can quickly develop a new application.
- A Temp&Pressure Logger and Analog voltage Logger application that demonstrates how you can quickly develop your own custom logging application using the onboard AT45D DataFlash.
Atmel ATmega328P Scorpion Board – [Link]
Ralph Doncaster writes:
Since the release of V-USB, dozens of projects have been made that allow an AVR to communicate over USB. USB data signals are supposed to be in the range of 2.8 to 3.6V, so there are two recommended ways to have an AVR output the correct voltage. One is to supply the AVR with 3.3V power, and the other is to use 5V power but clip the USB data signal using zener diodes. Most implementations of V-USB, like USBasp, use the zener diodes. I’ll explain why using a 3.3V supply should be the preferred method.
USB interfacing for AVR microcontrollers – [Link]
Davide Gironi published a new project an AVR ATmega328 based CO2, temperature and humidity logger and meter:
It logs data feed, CO2 in air in terms of ppm, temperature and humidity to a xively.com feed.
It also display realtime data to user through a 16×2 characters LCD.
This logger it is based on the xively logger you can found here
CO2 meter and Xively logger with NDIR infrared sensor built on AVR ATmega328 – [Link]
by George Gardner @ georgegardner.info:
This is a project that I’ve been working on for some time now, a good part of my life, but more recently for the past month. I’m not going to go through everything as to how I arrived at this point, but I can assure you it was through a lot of trial and error. I now present to you, the class D avr amp.
Class D AVR – [Link]