Texas Instruments MSP430x4xx - Manual (Page 462)

Scan IF Introduction
24-2 Scan IF
24.1 Scan IF Introduction
The Scan IF module is used to automatically measure linear or rotational
motion with the lowest possible power consumption. The Scan IF consists of
three blocks: the analog front end (AFE), the processing state machine (PSM),
and the timing state machine (TSM). The analog front end stimulates the
sensors, senses the signal levels and converts them into their digital
representation. The digital signals are passed into the processing state
machine. The processing state machine is used to analyze and count rotation
or motion. The timing state machine controls the analog front end and the
processing state machine.
The Scan IF features include:
- Support for different types of LC sensors
- Measurement of sensor signal envelope
- Measurement of sensor signal oscillation amplitude
- Support for resistive sensors such as Hall-effect or giant
magneto-resistive (GMR) sensors
- Direct analog input for A/D conversion
- Direct digital input for digital sensors such as optical decoders
- Support for quadrature decoding
The Scan IF module block diagram is shown in Figure 24−1.