Datasheet
SPRS161K − MARCH 2001 − REVISED JULY 2007
39
POST OFFICE BOX 1443 • HOUSTON, TEXAS 77251−1443
general-purpose (GP) timers
There are two GP timers. GP timer x (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 Internal input clock
D A programmable prescaler for internal clock input
D Control and interrupt logic, for four maskable interrupts: underflow, overflow, timer compare, and period
interrupts
The GP timers can be operated independently or synchronized with each other. The compare register
associated with GP timer 2 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. An internal input
clock 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, and GP timer 2/1 for the capture
unit. 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 the event manager (EVA). 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 16 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 eight PWM waveforms (outputs) can be generated simultaneously by EVA: three independent pairs (six
outputs) by the three full-compare units with programmable deadbands, and two independent PWMs by the
GP-timer compares.