LM3S9B81 Datasheet, PDF (58/1155 Pages) Texas Instruments – Stellaris® LM3S9B81 Microcontroller

Architectural Overview
1.1.5.3
1.1.5.4
– Reset pin assertion
– Brown-out reset (BOR) detector alerts to system power drops
– Software reset
– Watchdog timer reset
– MOSC failure
Four Programmable Timers (see page 423)
Programmable timers can be used to count or time external events that drive the Timer input pins.
Each GPTM block provides two 16-bit timers/counters that can be configured to operate independently
as timers or event counters, or configured to operate as one 32-bit timer or one 32-bit Real-Time
Clock (RTC). Timers can also be used to trigger analog-to-digital (ADC) conversions.
The General-Purpose Timer Module (GPTM) contains four GPTM blocks with the following functional
options:
■ Count up or down
■ 16- or 32-bit programmable one-shot timer
■ 16- or 32-bit programmable periodic timer
■ 16-bit general-purpose timer with an 8-bit prescaler
■ 32-bit Real-Time Clock (RTC) when using an external 32.768-KHz clock as the input
■ Eight Capture Compare PWM pins (CCP)
■ Daisy chaining of timer modules to allow a single timer to initiate multiple timing events
■ ADC event trigger
■ User-enabled stalling when the controller asserts CPU Halt flag during debug (excluding RTC
mode)
■ 16-bit input-edge count- or time-capture modes
■ 16-bit PWM mode with software-programmable output inversion of the PWM signal
■ Ability to determine the elapsed time between the assertion of the timer interrupt and entry into
the interrupt service routine.
■ Efficient transfers using Micro Direct Memory Access Controller (µDMA)
– Dedicated channel for each timer
– Burst request generated on timer interrupt
CCP Pins (see page 430)
Capture Compare PWM pins (CCP) can be used by the General-Purpose Timer Module to time/count
external events using the CCP pin as an input. Alternatively, the GPTM can generate a simple PWM
output on the CCP pin.
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June 29, 2010
Texas Instruments-Advance Information