Texas Instruments MSP430x4xx - Manual (Page 474)

Scan IF Operation
24-14 Scan IF
24.2.2 Scan IF Timing State Machine
The TSM is a sequential state machine that cycles through the SIFTSMx
registers and controls the analog front end and sensor excitation automatically
with no CPU intervention. The states are defined within a 24 x 16-bit memory,
SIFTSM0 to SIFTSM23. The SIFEN bit enables the TSM. When SIFEN = 0,
the ACLK input divider, the TSM start flip-flop, and the TSM outputs are reset
and the internal oscillator is stopped. The TSM block diagram is shown in
Figure 24−8.
The TSM begins at SIFTSM0 and ends when the TSM encounters a SIFTSMx
state with a set SIFTSTOP bit. When a state with a set SIFSTOP bit is reached,
the state counter is reset to zero and state processing stops. State processing
re-starts at SIFTSM0 with the next start condition when SIFTSMRP = 0, or
immediately when SIFTSMRP = 1
After generation of the SIFSTOP(tsm) pulse, the timing state machine will load
and maintain the conditions defined in SIFTSM0. In this state SIFLCEN(tsm)
should be reset to ensure that all LC oscillators are shorted.