Datasheet

edge time and PWM mode, the prescaler always acts as a timer extension, regardless of the count
direction.
Table 16-3. General-Purpose Timer Capabilities
Prescaler Size
a
Counter SizeCount DirectionTimer UseMode
8-bit16-bitUp or DownIndividual
One-shot
-32-bitUp or DownConcatenated
8-bit16-bitUp or DownIndividual
Periodic
-32-bitUp or DownConcatenated
-32-bitUpConcatenatedRTC
8-bit16-bitUp or DownIndividualEdge Count
8-bit16-bitUp or DownIndividualEdge Time
8-bit16-bitDownIndividualPWM
a. The prescaler is only available when the timers are used individually
Software configures the GPTM using the GPTM Configuration (GPTMCFG) register (see page 1124),
the GPTM Timer A Mode (GPTMTAMR) register (see page 1125), and the GPTM Timer B Mode
(GPTMTBMR) register (see page 1129). When in one of the concatenated modes, Timer A and Timer
B can only operate in one mode. However, when configured in an individual mode, Timer A and
Timer B can be independently configured in any combination of the individual modes.
16.3.1 GPTM Reset Conditions
After reset has been applied to the GPTM module, the module is in an inactive state, and all control
registers are cleared and in their default states. Counters Timer A and Timer B are initialized to all
1s, along with their corresponding registers:
■ Load Registers:
– GPTM Timer A Interval Load (GPTMTAILR) register (see page 1151)
– GPTM Timer B Interval Load (GPTMTBILR) register (see page 1152)
■ Shadow Registers:
– GPTM Timer A Value (GPTMTAV) register (see page 1161)
– GPTM Timer B Value (GPTMTBV) register (see page 1162)
The following prescale counters are initialized to all 0s:
■ GPTM Timer A Prescale (GPTMTAPR) register (see page 1155)
■ GPTM Timer B Prescale (GPTMTBPR) register (see page 1156)
■ GPTM Timer A Prescale Snapshot (GPTMTAPS) register (see page 1164)
■ GPTM Timer B Prescale Snapshot (GPTMTBPS) register (see page 1165)
16.3.2 Timer Clock Source
The general purpose timer has the capability of being clocked by either the system clock or an
alternate clock source. By setting the ALTCLK bit in the GPTM Clock Configuration (GPTMCC)
December 13, 20131106
Texas Instruments-Advance Information
General-Purpose Timers