Motorola ColdFire MCF5281 - Manual (Page 369)

Freescale Semiconductor 20-1
Chapter 20
General Purpose Timer Modules (GPTA and GPTB)
The processor has two 4-channel general purpose timer modules (GPTA and GPTB). Each consists of a
16-bit counter driven by a 7-stage programmable prescaler.
A timer overflow function allows software to extend the timing capability of the system beyond the 16-bit
range of the counter. Each of the four timer channels can be configured for input capture, which can
capture the time of a selected transition edge, or for output compare, which can generate output waveforms
and timer software delays. These functions allow simultaneous input waveform measurements and output
waveform generation.
Additionally, one of the channels, channel 3, can be configured as a 16-bit pulse accumulator that can
operate as a simple event counter or as a gated time accumulator. The pulse accumulator uses the GPT
channel 3 input/output pin in either event mode or gated time accumulation mode.
20.1 Features
Features of the general-purpose timer include:
• Four 16-bit input capture/output compare channels
• 16-bit architecture
• Programmable prescaler
• Pulse widths variable from microseconds to seconds
• Single 16-bit pulse accumulator
• Toggle-on-overflow feature for pulse-width modulator (PWM) generation
• External timer clock input (SYNCA/SYNCB)
MCF5282 and MCF5216 ColdFire Microcontroller User’s Manual, Rev. 3