Programmable Timer Design - From concept to board

Programmable Timer Design Using PIC12F629 Microcontroller

As part of my embedded systems development work, I designed a compact programmable timer module based on the PIC12F629 microcontroller. This timer is intended for use in automation systems, industrial control panels, laboratory equipment, and custom electronic projects where accurate and configurable timing control is required.

The device allows users to set alarm timings according to specific application requirements. Once the desired time value is configured, the timer counts up and triggers the alarm output when the preset value is reached. This makes the module useful for tasks such as delayed switching, process timing, equipment control, and notification systems.

To provide a clear visual interface, the timer uses two seven-segment displays (SSD) to show the configured time values. The display allows users to easily monitor the current timer settings and countdown status. The display system is optimized to operate efficiently with the limited I/O resources available in the microcontroller.

User interaction with the device is intentionally designed to be simple and intuitive. The timer settings can be adjusted using two push buttons, which allow the user to increase or modify the time values without the need for complex controls or external programming tools. This minimal interface reduces hardware complexity while maintaining ease of use.

The firmware running inside the PIC12F629 manages display multiplexing, button input detection, and timing control. The design focuses on low component count, reliable operation, and compact circuit implementation, making it suitable for embedded applications where space and cost are important considerations.

This type of programmable timer can be easily integrated into custom electronics projects, automation controllers, sensor systems, and industrial devices. The design also demonstrates how small microcontrollers can be effectively used to build practical control modules with minimal hardware.

Download firmware, schematic diagram and operating instructions using following links.

Operating instructions - PDF file

Schematic diagram - Schematic image

Firmware files - Microchip XC8 project files

PCB files - Eagle 7.6

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