Texas Instruments MSP430x4xx - Manual (Page 437)

SD16_A Operation
22-11 SD16_A
22.2.9 Conversion Modes
The SD16_A module can be configured for two modes of operation, listed in
Table 22−3. The SD16SNGL bit selects the conversion mode.
Table 22−3.Conversion Mode Summary
SD16SNGL Mode Operation
1 Single conversion The channel is converted once.
0 Continuous conversion The channel is converted continuously.
Single Conversion
Setting the SD16SC bit of the channel initiates one conversion on that channel
when SD16SNGL = 1. The SD16SC bit will automatically be cleared after
conversion completion.
Clearing SD16SC before the conversion is completed immediately stops
conversion of the channel, the channel is powered down and the
corresponding digital filter is turned off. The value in SD16MEM0 can change
when SD16SC is cleared. It is recommended that the conversion data in
SD16MEM0 be read prior to clearing SD16SC to avoid reading an invalid
result.
Continuous Conversion
When SD16SNGL = 0 continuous conversion mode is selected. Conversion
of the channel will begin when SD16SC is set and continue until the SD16SC
bit is cleared by software.
Clearing SD16SC immediately stops conversion of the selected channel, the
channel is powered down and the corresponding digital filter is turned off. The
value in SD16MEM0 can change when SD16SC is cleared. It is recommended
that the conversion data in SD16MEM0 be read prior to clearing SD16SC to
avoid reading an invalid result.
Figure 22−6 shows conversion operation.
Figure 22−6. Single Channel Operation
SD16SNGL = 1
Time
Conversion
SD16SC
SD16SNGL = 0
Conversion
SD16SC
Conversion Conversion
Set by SW Auto−clear
Set by SW
Conv
Cleared by SW
= Result written to SD16MEM0