TMS320F243_15 Datasheet, PDF (51/122 Pages) Texas Instruments – DSP CONTROLLERS

TMS320F243, TMS320F241
DSP CONTROLLERS
SPRS064D − DECEMBER 1997 − REVISED FEBRUARY 2006
general-purpose (GP) timers
There are two GP timers on the TMS320x24x. The GP timer x (for x = 1 or 2) includes:
D A 16-bit timer, up-/down-counter, TxCNT, for reads or writes
D A 16-bit timer-compare register, TxCMPR (double-buffered with shadow register), for reads or writes
D A 16-bit timer-period register, TxPR (double-buffered with shadow register), for reads or writes
D A 16-bit timer-control register,TxCON, for reads or writes
D Selectable internal or external input clocks
D A programmable prescaler for internal or external clock inputs
D Control and interrupt logic, for four maskable interrupts: underflow, overflow, timer compare, and period
interrupts
D A selectable direction input pin (TDIR) (to count up or down when directional up- / down-count mode is
selected)
The GP timers can be operated independently or synchronized with each other. The compare register
associated with each GP timer can be used for compare function and PWM-waveform generation. There are
three continuous modes of operations for each GP timer in up- or up / down-counting operations. Internal or
external input clocks with programmable prescaler is used for each GP timer. GP timers also provide the time
base for the other event-manager submodules: GP timer 1 for all the compares and PWM circuits, GP timer 2/1
for the capture units and the quadrature-pulse counting operations.
Double-buffering of the period and compare registers allows programmable change of the timer (PWM) period
and the compare/PWM pulse width as needed.
full-compare units
There are three full-compare units on TMS320x24x. These compare units use GP timer1 as the time base and
generate six outputs for compare and PWM-waveform generation using programmable deadband circuit. The
state of each of the six outputs is configured independently. The compare registers of the compare units are
double-buffered, allowing programmable change of the compare/PWM pulse widths as needed.
programmable deadband generator
The deadband generator circuit includes three 8-bit counters and an 8-bit compare register. Desired deadband
values (from 0 to 24 µs) can be programmed into the compare register for the outputs of the three compare units.
The deadband generation can be enabled/disabled for each compare unit output individually. The
deadband-generator circuit produces two outputs (with or without deadband zone) for each compare unit output
signal. The output states of the deadband generator are configurable and changeable as needed by way of the
double-buffered ACTR register.
PWM waveform generation
Up to 8 PWM waveforms (outputs) can be generated simultaneously by TMS320x24x: three independent pairs
(six outputs) by the three full-compare units with programmable deadbands, and two independent PWMs by
the GP-timer compares.
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