Projects

In past years I made lot of electronics constructions. Some of them were made on proto-board, some of them were reassembled as they get working properly and become uninterest for me. From that bunch of projects I'll present some here

CAR MONITOR- This device monitor 16 digital values in car and events display on LCD module. This action is follow by sound alert. Inputs can be fuel level, temperature overflow, door closing signalization... This is 68HC11 project. Here are source, PCB (Protel) and schematic.

ETAI 11- Hart of this project is 68HC11E2. This devide measure impulses from three inputs (Interrupt driven). Those tree values represent three axes of rotor digger. Measured values are display on LED display.Display is attached at SPI port, and source you can find here.

ROBO 1 - Well, this is my first robot. Features are poor but I'm very satisfied with him. ROBO 1 just rolling around and when touch something with his antenna it pull back and change direction opposite to barrier. This is also 68HC11 project. Source code you can find here and also schematic of motor driver board with aditional elements which are not used in this project (stepper motor drivers).

Other projects

Ultrasonic distance meter - How to hack Polaroid's distance meter from one-step Polaroid camera. Modul is interfaced with 68HC11. Here is schematic and source code.Useful links are here.

Stepper Motor Driver - This board can work as stand-alone with bilt-in takt generator or controlling by external device. I made the example for 68HC11.

AVR Demo Board:

If you want to do some experimentes with AVR MCU I will recommend you to bild this simple evolution board for AT90S1200 and AT90S2313. Here is PCB . Schematic diagram is very simple becouse isn't show here. When you assembled board use this test program to test functionality of the board. Connect LEDs on PORTB and PORTD and thay will swiching one by one on one port and after that on the other port.

iButtons:

Here is my research about iButton memories and 1-wire protocol. Basics are in application note from Dallas Semiconductors app74. On page 21 yuo can find interface for RS-232. TMEX program you can find on that site too. Also, if you prefer finished solution, read my article published in magazine "Mikroelektronika".

Serial Communication PC <-> MCU:

For this experiment you must have PC program which will send and receive bytes you like, or programmed MCU with the same job. I start to bild application in Visual Basic 6 (everybody works in it, so I decide to use VB6 too). First I made simple program for AVR 90S2313 in BASCOM Basic. Here is HEX. In last time I use PonyProg for programming my AVR's. Visual Basic program is named Serial Example. Of course, you'll need appropriate *.dll & *.ocx files. Here what it do: In text box you type number 33 and press button SEND, MCU receive this byte , inspect is it 0x33, and if so send back, to PC, five bytes 0x01, 0x02, 0x03, 0x04 and 0x05. Those five bytes are present in second text box.

PDA:

Palm computers are very interesting for developers becouse thay have almost everything you need in one place: processor, grafic display, power supply, serial communication, IrDA port ect. As a Motorola's fan the most close to me is PDA from Palm company vith Motorola's DragonBall inside. I find on net only one interesting enviroment for applications develop from AppForge. Thay give 30-day free evolution copy. When I made sample as it is in previos paragraph it didn't receive anything. I spend few days studing other samples and manuals but without success. I wrote to AppForge Suport Centre but no respose. I wonder what will be if I bought this soft for $700?

Flow meter:

Here is little project that I intend to use for measuring fuel flow in my Renault 5 GTS. I use turbine sensor which gives 1800 pulses/liter supplied from CONRAD. Ordering number is 18 71 51. MCU is AVR 90S2313 and results are display on LCD module 2x10 characters. I wrote source in BASCOM (thanks Mark). You also can find schematic in *.pdf. when I finish I tested it in car and I get wrong result. I have error more then 50%. In case of free fall measuring it work OK. The problem is vibration fuel pump. That I see in manufacturer web site (DIGMESA FHKSC type).Motor vibrations and interferences from ignition system are not sources of this problem. I was not able to check this becouse CONRAD never expose those source. When you buy you can see logo on product but then is too late.

Humidity and Temperature meter:

Sensirion make fine SHT-11 sensors for humidity and temperature measuring. Sensors for this exist long time ago exept this is the sensor with digital output.There is no need for calibration, only you have to do is to calculate values from readout. Resolution can be choose between 12-bit humidity and 14-bit temperature (default) or 8-bit humidity and 12-bit temperature. Only 4 wires are necessary for interface to host MCU: Power supply (2.4 to 5.5V), GND, SCK and DATA. On first sight it looks as I2C communication but it isn't. Sensirion made there own protocol called SENSI-BUS. I made code in BASCOM for AVR and spend a lot of time to understand data sheet and apply it.