MC68336/376
TIME PROCESSOR UNIT
MOTOROLA
USER’S MANUAL
Rev. 15 Oct 2000
11-2
Pulse width modulation
Synchronized pulse width modulation
Period measurement with additional transition detect
Period measurement with missing transition detect
Position-synchronized pulse generator
Stepper motor
Period/pulse width accumulator
Quadrature decode
The G mask set (or motion control mask set) includes the following functions:
Table stepper motor
New input capture/transition counter
Queued output match
Programmable time accumulator
Multichannel pulse width modulation
Fast quadrature decode
Universal asynchronous receiver/transmitter
Brushless motor communication
Frequency measurement
Hall effect decode
11.2 TPU Components
The TPU consists of two 16-bit time bases, sixteen independent timer channels, a task
scheduler, a microengine, and a host interface. In addition, a dual-ported parameter
RAM is used to pass parameters between the module and the CPU32.
11.2.1 Time Bases
Two 16-bit counters provide reference time bases for all output compare and input
capture events. Prescalers for both time bases are controlled by the CPU32 via bit
fields in the TPU module configuration register (TPUMCR). Timer count registers
TCR1 and TCR2 provide access to the current counter values. TCR1 and TCR2 can
be read by TPU microcode, but are not directly available to the CPU32. The TCR1
clock is derived from the system clock. The TCR2 clock can be derived from the sys-
tem clock or from an external clock input via the T2CLK pin.
11.2.2 Timer Channels
The TPU has 16 independent channels, each connected to an MCU pin. The channels
have identical hardware. Each channel consists of an event register and pin control
logic. The event register contains a 16-bit capture register, a 16-bit compare/match
register, and a 16-bit greater-than-or-equal-to comparator. The direction of each pin,
either output or input, is determined by the TPU microengine. Each channel can either
use the same time base for match and capture, or can use one time base for match
and the other for capture.