PIC Based Message wand
The project uses flashing LEDs to present shot message in the air by swinging a wand around above the head.
A perfboard is used to construct the circuit that is powered by 2 coin cells type CR2016. The power fluctuations from excessive load on the coin cells can be prevented using the electrolytic capacitor. A toothbrush holder is used to make the message wand since swinging around the exposed sharp edges of circuit boards and batteries is dangerous.
The method of table look-up in a PIC is featured by the message wand program. Depending on the user requirements, the table that holds the message can be modified since it is in the form of pixel data. Synchronization is not used since the message is repeated at a fixed rate of about 3 times per second.
The mid-range PIC16F627 microcontroller is used by the message wand where one of its I/O lines is only capable of using a digital output and one is only capable of driving open drain. To ensure the internal oscillator of the PIC is running at about 4MHz, a register bit is implemented and addressed by wand.asm file.
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