Numitron display based digital clock

I bet you like Nixie clocks and probably wouldn’t mind to have one on your table. Anyway, Nixie displays require relatively high voltage to light segments. But if you don’t want to generate higher voltages but rather stay with 5V then you should consider numitron displays. These vacuum tube displays light up from like 5V. Pinomelean purchased several of IV-9 displays and wanted to build very simple digital clock. Instead of making full number display he used single digit to tell time. The method is pretty simple – it displays hours and minutes one by one. Four additional LEDs allow easy tracking of current digit displayed. Clock is driven by PIC16F84A microcontroller which is clocked at 4MHz. Using one digit display saves space and allows to design small device. For basic time monitoring this is more than enough.   Continue reading

Digital clock as we know it

Sometimes we just need a simple digital clock without fancy features and schematic. So manelsoft simply found textbook PIC based digital clock and built it. Clock uses PIC16F84A microcontroller driven by 4MHz crystal clock source. Time is displayed on 6 seven segment LED display controlled through CD4017 decade counter and common cathode transistors. Clock can be set with two available push-buttons. Source code and other necessary files are available to download and have it running right away. Continue reading

PlayPIC: A PIC16F84A based trainer to play with

When we were still kids (not so long ago for me) we were trained to walk using wheeled walking aids, when we started preschool we have those plastic template for us to trace drawings. Well in the world of electronics and microcontrollers the case is similar – they don’t give you something an electronic aid or something instead they have things called trainers – these stuff is where you could practice both your electronics and programming skills keeping you tuned for the challenging project that awaits! This simple project aims just to give you the practice that you need. Based on the popular PIC16F84A microcontroller it’s jam-packed with the input and output options to hone your microcontroller programming. It has eight single Leds, a seven segment display, five push buttons and something that every project should have – LCD! It takes the beginner to a step further into the world of microcontrollers. One of the most important features of PlayPIC is that it has an in-circuit-programming header which means you could reprogram the microcontroller without unplugging it out of the… Continue reading

PicOClock an expensive way to tell time using a PIC16F84A

I know most of you guys have already seen/used/dismantled/damaged an oscilloscope, well for me the oscilloscope is the rectangular box with a small TV screen with green curves that we use in the laboratory, to have a clear description of the oscilloscope I checked wiki – and it says: “An oscilloscope is a type of electronic test instrument that allows observation of constantly varying signal voltages, usually as a two-dimensional graph of one or more electrical potential differences using the vertical or ‘Y’ axis, plotted as a function of time.” Bruno Gavand got this neat idea of using his high tech scope to display time by using a PIC16F84A microcontroller. Using four resistors configured to operate like a 2bit R-2R DAC Bruno could control the Y-axis of the scope’s plot while using pulse width modulation on the trigger line to control the timing. By using both timing and Y axis controls together Bruno was able to display numeric values in a scope. It also comes with two push buttons, one for hours and one for minutes. Talk about expensive way… Continue reading

A digital thermometer using PIC16F84A and DS18B20

There are a lot commercially available digital thermometers in the market but why buy when you can build one? This project is very straight forward; it uses a PIC16F84A microprocessor and Dallas Maxim’s DS18B20 programmable resolution 1 wire digital thermometer to measure the temperature. The PIC16F84A is used to set the digital thermometer’s resolution and to read the temperature data using 1-Wire interface. Two 7-segment displays were used as the temperature indicator. The DS18B20 is capable of measuring temperatures from -55 to 125 degrees Celsius however the rest of the other components are not rated to operate at the temperature extremes. The device can still be used to measure the extremes of the range given that only the DS18B20 is exposed to the very hot/cold temperature. Continue reading

Tiny GSM Alarm System – The Smart and Portable Sensor Trigger

Did anyone here ever get in touch with the GSM call alarm or GSM SMS alarm before? If you did, then the Tiny GSM alarm system is going to be the masterpiece combination of the call alarm and SMS alarm! The main purpose of the tiny GSM alarm system is a device, which is can be used to operate standalone or as a module for existing alarm system. The tiny GSM alarm system is much more advanced than the previous, as it’s not only can arm or disarm the system with “enable” pin, but you can do the same task by simply calling from your own phone! Sounds like a cool add-on, isn’t it? Well, the tiny GSM alarm system is built on a very popular microcontroller, the PIC16F84A. In this case, you don’t have to bother with external EEPROM memory for SMS storage, as you have the option to use phone’s SIM SMS storage and phonebook memory for the storage task! Well, the GSM phone that is best compatible with the device is Siemens M35i. To be honest, it’s… Continue reading