Texas Instruments MSP430x4xx - Manual (Page 391)

ADC12 Operation
20-15 ADC12
Using the Multiple Sample and Convert (MSC) Bit
To configure the converter to perform successive conversions automatically
and as quickly as possible, a multiple sample and convert function is available.
When MSC = 1, CONSEQx > 0, and the sample timer is used, the first rising
edge of the SHI signal triggers the first conversion. Successive conversions
are triggered automatically as soon as the prior conversion is completed.
Additional rising edges on SHI are ignored until the sequence is completed in
the single-sequence mode or until the ENC bit is toggled in
repeat-single-channel, or repeated-sequence modes. The function of the ENC
bit is unchanged when using the MSC bit.
Stopping Conversions
Stopping ADC12 activity depends on the mode of operation. The
recommended ways to stop an active conversion or conversion sequence are:
- Resetting ENC in single-channel single-conversion mode stops a
conversion immediately and the results are unpredictable. For correct
results, poll the busy bit until reset before clearing ENC.
- Resetting ENC during repeat-single-channel operation stops the
converter at the end of the current conversion.
- Resetting ENC during a sequence or repeat-sequence mode stops the
converter at the end of the sequence.
- Any conversion mode may be stopped immediately by setting the
CONSEQx = 0 and resetting ENC bit. Conversion data are unreliable.
Note: No EOS Bit Set For Sequence
If no EOS bit is set and a sequence mode is selected, resetting the ENC bit
does not stop the sequence. To stop the sequence, first select a
single-channel mode and then reset ENC.