Bajdi blogged about his Arduino pro mini undershield:
I’ve designed another PCB This time it’s a simple undershield for the Arduino pro mini. I received the PCB’s from Electrodragon (12$ for 10PCB’s) last week. The PCB has a schottky diode and a 5V linear regulator, I’m using an LM2940 5V regulator. For the rest there are just 2 rows of female headers to plug the pro mini in and 3 rows of male pins on each side.
The reason I’ve had this PCB made is that pro mini’s are dirt cheap these days, you can find them on Ebay or Chinese shops for mess then 4$. That makes them the cheapest Arduino on the internet. It’s cheaper and easier to buy a pro mini and integrate it in to your own project then to design your own PCB with an ATmega328.
Arduino pro mini undershield - [Link]
bgyroscope @ www.instructables.com writes:
This instructable will show you how to build your own stopwatch to record multiple splits using an ATmega328 programmable microcontroller. When one presses the start button (or slaps the metal band in my watch), the screen displays the last lap for a second then continues the time on the next lap. It’s great for all you runners out there doing an interval workout.
Lap Stopwatch with ATmega328 Microcontroller - [Link]
Evilthingamabober @ instructables.com writes:
Microcontrollers are, without a doubt, amazing little things. They are versatile, powerful, and extremely tiny. Unfortunately, the latter trait is also shared by both my wallet and my programming skills. My understanding of C is poor, and I can hardly afford to buy something like an Arduino or a decent ISP. And in any case, the Arduino would be overkill for many of my projects, which only need simple IC’s.
But as many of you know, DIY always finds a way. This tutorial is meant for those among us with no budgets or programming experience who want to start using these little machines. It is not based around the ATmega328 (the Arduino Uno chip), but rather the Attiny line of chips (the Atiny85 and Attiny2313, to be specific). The total cost of this project can go as lower than $15 if you know where to buy from, and you can still use the original Arduino IDE and language to program your projects in the end. Keep in mind that you will need some soldering skills to get this project done.
The Idiot’s Guide to Programming AVR’s on the Cheap - [Link]
ARPix has posted this instructable on constructing an external serial monitor device using the Atmega328 MCU and a graphic LCD. It allows a user interface to set the serial baud rate and start/stop functions using tact switches.
Sometimes I needed an external serial monitor like the Serial Monitor in the Arduino Editor, to see what is going on. So I made one. For the ESM I used an Atmel Atmega328 because it have an internal SRAM with 2KBytes. It’s necessary for the big data processing. So you need more than 1KByte SRAM.
Constructing an external serial monitor - [Link]
Gert van Loo, the Broadcom employee responsible for the RPi alpha build has now come up with the Gertduino. He also gave us the GertBoard GPIO Expansion board some time ago which provides general purpose I/Os, LEDs and motor driver capabilities for the Rpi. Gert’s latest creation, the Gertduino board, plugs onto the RPi and connects it to virtually any existing Arduino Shield. The board itself basically offers the same functionality as the Arduino-Uno but with some added features thrown in.
As well as an ATmega328 and ATmega48 (both of which can be programmed from the Raspberry Pi using the Arduino GUI or the GCC Atmel compiler), the Gertduino packs a real time clock, 16MHz oscillator, IRDA interface, RS232 level converter and a battery back-up power supply for the ATmega48.
Gertduino: The Raspberry Pi /Arduino Missing Link - [Link]
Bajdi documented his Arduino self balancing bot build:
For the electronics I used one of my own PCB creations, a Bajduino of course It’s just a small (50x50mm) break out board for an ATmega328. I’m running the ATmega @ 16MHz and 3.3V. It’s out of spec according to the datasheet but it works… I also needed an IMU of course. I found a MP6050 sensor in my parts box. The MPU6050 combines a 3 DOF gyro and 3 DOF accelerometer in a small package, ideal for a self balancing bot.
Building a self balancing bot - [Link]
BO.Duino is an Arduino compatible board based on ATmega328 ATMEL’s mcu. This board features many peripherals usually externally connected on a breadboard or prototyping board such as sensors, SD card etc. Peripherals included are:
– A real-time clock
– AT24 series external memory chip
– MicroSD card adaptor (SPI)
– RGB LED
– A potentiometer on analog input
– Connector for DS18b20 or DHt11 series sensors
BO.Duino – ATmega328 Arduino Compatible board - [Link]
This video by Ray Wang demonstrates HID-class USB serial communication for AVRs using the V-USB library:
Serial communication is helpful for debugging and checking sensor values, and HID-class means it can work on all operating systems without driver installation. This is useful for many software-only USB projects such as based on ATmega328 or ATtiny45/85. To receive and send messages between the device and host, I wrote an HID serial monitor, similar to a standard serial monitor, using Processing.
HID-class USB Serial communication for AVRs using V-USB - [Link]
Web-based relay controller for home automation.
Home automation is getting increasingly popular these days mainly due to reduced cost and simplicity through web or smartphone connectivity. Here’s a DIY version of web-based home automation controller that allows you to have a set of six relays connected to the end of a piece of Ethernet cable that can be accessed from a web browser anywhere from your house. You can use it to control or program the operation of lights, water pumps, or any other electrical appliances at home. The project uses Arduino (Atmega328) microcontroller and the ENC28J60 ethernet controller chipset.
Web-based relay controller for home automation - [Link]
Learn how to load Arduino bootloader on a ATMEGA328 IC using ISP programmer and Arduino board. randofo @ instructables.com writes:
Bootloading an Arduino with a ZIF socket allows you to easily program a lot of chips at once without worrying about mangling the pins. The reason for this is that ZIF stands for “zero insertion force,” and as the name implies, ZIF sockets don’t require any force to take the chip in or out. This means that you do not have to worry about any of the pins bending when you take the chip in and out of the socket. This is particularly useful if you need to bootload a lot of Arduino chips at once for inclusion in an electronics kit or if you need to repeatedly program a chip and transfer it back and forth between a separate circuit board.
Bootload an Arduino with a ZIF Socket - [Link]