Timers and PWM

64 Minus 2 Simulator

This program will work on all Timer A versions of the M16C family including M16C/Tiny, 62P, 30P, and other Timer A equipped MCUs. This simple program simulates a 64-2 timing wheel for some Ford/GM model automobiles. There are 2 missing teeth on a typical timing wheel which allows the automotive computer to determine which bank of spark plugs to fire. This program uses timer A in event counter mode to sample a square wave input into the timer A pin (TA0IN). This input signal causes the timer to countdown until the timer underflows. At this point the timer interrupt triggers and the I/O port (P10_0) is toggled. Once the toggle count reaches 62 pulses, the I/O port is stopped at a 'L' level and the timer continues to count until it reaches 64 pulses. At this point the pulse train is restarted and the cycle continues.

Input capture timer example.

This design provides a good example of using the input capture features of the M16C timers.

More timer examples.

This projects uses timers on the M32C to control the ADC, control sine wave data for DTMF tone generation, and as a Real Time Clock.

PWM of 7 segment LEDs.

This project uses a PWM channel to control brightness on 7 segment LED displays.

Timer controlled DMA

This project uses system timers to control DMA channels. This project makes heavy use of DMA.

Timer examples

This reference design provides code to use Timer B in Input Capture mode. Other timers are also used for various functions.

Timer generates system tick.

This project uses a timer resource to generate a system tick and control PWM generation.

Timer used to create beeps and timed delays.

This project uses timers to create various simple beeps as well as delay time functions.

Timer used to create system tick/interrupt.

This project uses a timer to create a system tick.

Tone Generation.

This example project uses the PWM to generate various tones.

TRIAC control of heating element.

This project uses a PWM channel to control a Triac and AC heating element. The code also includes a simple PID loop.

Vee bias voltage generation for LCDs

This project uses a PWM channel to generate the Vee bias voltage for a graphic LCD display.

Simple PWM using DMA & Timer

The sample code in "62P_DMA_Fwd_Src_Repeat_w_Timer" shows how to set up multiple channel simple PWMs using a DMA and a timer. The concept enables the generation of PWM signals on multiple ports without involving the MCU core touching the timer or DMA peripheral. Only the RAM value 'data_src' for the PWM values needs to be changed by the application. The rest of the actual PWM generation runs once set up.