AUG31
Connecting thermal printer with AVR
This is actually a thermal printhead, not a printer. Connecting a printer would be much easier; just send it some AT commands and it will print your data. In this case the author had to implement "font" in firmware, control two servo motors and the burning dots on the printhead itself.
The microcontroller of choice is AVR with Arduino bootloader. The burning dots (heating elements) are controlled with ULN2801A darlington transistors array which is in turn controlled by SN74164 shift register to save many IO pins. See the video of the printer in action after the break.
Source: Manuel Rábade
AUG23
POV Propeller Clock Build
Here are a few pictures and videos of the latest project of our forum member [Kizo].
It is a POV propeller clock and it just might be the best one yet! Firmware is written in Bascom-AVR and consists of around 3000 lines of code. The power between the motor and the rotating electronics is transferred wirelessly (see the second video).
"Parts list: ATmega324P @ 20MHz, 64kb Ramtron FRAM, FM1608, 5 x TLC5916 constant current LED drivers, 40 x Cyan PLCC-4 LEDs, A1101 Hall IC, TSOP6238 IR receiver and MIC5209-5.0 LDO V-reg."
Source: Kizo
AUG11
Nixie clock in a model train
This Nixie Clock comes from [pezi666999] from Germany and it is originally a single nixie tube clock but in a slightly different housing.
The clock is put inside a model train (a model locomotive) and the tube is actually IN-8-2 with "dot mark" not used. You can see how it works in the video after the break, and you can also take a look at the original project page to make one yourself.
Source: pezi666999
AUG10
Digital clock/calendar/thermometer
Be sure not to miss this great digital clock with built-in calendar and thermometer!
This is a relatively small digital clock/calendar with thermometer based on Microchip PIC16F628 (or even PIC16F84) and DS18S20 or DS18B20 temperature sensor from Maxim-IC. The hardware part is very simple because it only uses PIC microcontroller, DS18S20/DS18B20 sensor, 4x7 segment LED display with common anode, four 2N3906 transistors, and some resistors.
Also you can find a digital thermostat project on the project page.
Source: Bogdan Borca
AUG3
New version of Protostack AVR board
This week Protostack released version 1.5 of their AVR development board. Like the previous version that we reviewed back in January, this one comes with a range of improvements... 6 in fact.
The power supply section has been updated to support voltage regulators with Input/Ground/Output pinouts and Ground/Output/Input pinouts. This is achieved by using 4 plated through holes (I G O I) and a strange looking figure of 8 shaped mounting hole. The new power supply block also includes a diode and resettable fuse to protect against reverse polarity and over current.
With better port labelling, a bigger dual row block and better labelling for a CR2032 battery connector, this improves what was already an excellent development board.
Source: Protostack
JUL9
Electromechanical Nixie Clock
We have seen the propeller nixie clock which was something new, but this nixie clock is really really something else.
There is no microcontroller to keep track of time and no tube multiplexing of any kind. The clock source is derived from a Telechron motor that does one revolution per minute. Seconds are displayed on IN-13 analog neon tube by using a potentiometer attached to the rotor and hours and minutes are produced with specially designed "gears" and PCB masks. This really is a piece of art!
Be sure to check the video after the break.
Source: Jon S. - electronix and more
JUL7
Nokia 3310 AVR library
With all these scrap phones and phone parts available nowadays, old Nokias in particular, it is very useful to learn how to interface reusable parts such as LCDs.
Microcontroller interfaced to 3310's LCD is ATmega8 and it also connects to USB port. LCD is based on Phillips PCD8544 controller and libraries are written in C. The source code also includes the "V-USB, virtual USB port for AVR microcontrollers" so LCD is actually controlled by a PC application.
Source: wkter
JUL1
AVR tutorial - IO registers
Protostack has announced their next AVR tutorial - "Introduction to I/O Registers". IO register is the way for microcontroller to interact with the outside world. So this tutorial will teach yout what are and how to use PORT, PIN and DDR registers on ATmega8.
The tutorial is, of course, in GCC.
Source: Protostack
