PIC 16F88 Microcontroller PIC based Tengu


Posted on Feb 6, 2014

Tengu derives its name from a mythicalJapanese creature known for getting intomischief. Our Tengu, however is more earthly in nature. It responds to voice and sounds and takes on different facial features depending on the intensity of the sound. If no sound is heard for some time, it changes from a happy face to a sad face and then goes to sleep. G


PIC 16F88 Microcontroller PIC based Tengu
Click here to download the full size of the above Circuit.

ently blowing on his face wakes him back up to his usual happy self. The project is based on a Microchip PIC 16F88 which is part of their mid range of microcontrollers. The sound is amplified through a pre-amp circuit based on 2N3904 and fed to the RB7/AN6 (pin 13) of the pic microcontroller. The A/D converter on the microcontroller is used to convert the analog signal from the pre-amp. The LED Matrix is directly driven by the pic. In order to be able to display the entire smiley, the LED dot matrix is multiplexed in such a way that only one row out of the seven is active at any given time. However the rows are turned on and off so rapidly, the human eye sees it as a full picture. This effect is called the persistence of vision. In order to achieve multiplexing, timer 0 on the pic is running at approximately 1 ms timeouts to switch the row that is being displayed on the LED Matrix. Timer 1 is configured as a general purpose timer used to keep track of the time since any noise over the threshold was heard. This is used to change the smiley from a happy to a sad one. The code is written in C using MPLAB and Hi-Tech C compiler ver 9. 80.




Leave Comment

characters left:

Related Circuits

  • New Circuits

    .

     


    Popular Circuits

    Add current boost to a USB charger
    Square wave generator III
    FM Transmitter 4Watt
    50mW BH1417 Stereo PLL FM Transmitter
    Whats the purpose of the diodes in this circuit
    remote control
    fet audio mixer circuit
    electronic toggle switch no1
    Audio Voice-Over Circuit PCB
    ZX Interface 2
    Thermometer meter slinger 2
    LM386 making music with a voice-activated lights circuit
    Sawtooth generator circuit a



    Top