This MSP430 Launchpad cyclic timer project is written by Shawon Shahryiar from MicroArena and describes a cyclic on/off timer switch with a standard character LCD for displaying the on/off time as well as the state of the switch, and which can be programmed through capacitive touch inputs. The On and Off times can be programmed separately and the timer cycles endlessly through the set times. Shawon uses the TTP224 integrated circuit to implement 4 capacitive touch inputs in the project. The firmware for the project was developed using Energia IDE and can be downloaded from the link at the end of the article.
Here is another countdown timer based on the PIC16F886 microcontroller. The timer displays the time on four bright 7-segment LEDs, which are driven by a TLC5916 LED driver chip. The timer flashes the seven segment LEDs when the time is up. The timer settings are done with a rotary encoder with a push button, and gets powered from two AAA batteries.
Mark Weir from Australia sent us his revision of our Programmable digital timer switch project. He modified the original code, which was written for PIC16F628A, to incorporate it with PIC18F4620 microcontroller, while hardware and overall functionality remain the same.
Digital timer using PIC18F4620
Here is a link to download his modified version of the firmware written in MikroC compiler.
Kevin Murphy from New Boston, Michigan is a regular reader of Embedded Lab. He adapted our digital timer project to fulfill his need of a programmable timer switch for his darkroom. Here are some pictures that he has sent us showing how his assembled PCB of this project look like.
Dark room timer
Dark room timer assembled board
He also received a PCB for the 18-pin PIC16F board from us last week. The following pictures shows his assembled breadboard module for PIC16F628.
PIC16F628 breadboard module
The board with an external power supply
Thank you, Kevin for sharing these pictures with us.
Last week I was browsing my old backup hard drive and I found a source code for a very simple PIC based digital timer that I made a couple of years ago. The actual hardware of the project isn’t with me anymore. I might have lost it when I moved from my old apartment into my new home. However, I thought this might be a good practice project for beginners and so I am sharing it here. I am not going to build it from scratch again; I will rather demonstrate it using my DIY PIC16F628A breadboard module and I/O board. The complete circuit diagram along with the firmware developed using mikroC Pro for PIC compiler is provided in the article.