MC68HC12 Datasheet, PDF (242/478 Pages) Motorola, Inc – The MC68HC912DT128A microcontroller unit (MCU) is a 16-bit device composed of standard on-chip peripherals including a 16-bit central processing unit

Enhanced Capture Timer
This design specification describes the standard timer as well as the
additional features.
The basic timer consists of a 16-bit, software-programmable counter
driven by a prescaler. This timer can be used for many purposes,
including input waveform measurements while simultaneously
generating an output waveform. Pulse widths can vary from
microseconds to many seconds.
A full access for the counter registers or the input capture/output
compare registers should take place in one clock cycle. Accessing high
byte and low byte separately for all of these registers may not yield the
same result as accessing them in one word.
Technical Data
242
Enhanced Capture Timer
MC68HC912DT128A — Rev 4.0
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