Texas Instruments MSP430x1xx - Manual (Page 299)

Conversion Modes
15-9
ADC12
15.5 Conversion Modes
The ADC12 has four conversion modes:
- Single-channel, single-conversion
- Single-channel, repeated-conversions
- Sequence-of-channels, single-sequence
- Sequence-of-channels, repeated-sequence
Each mode is summarized in Table 15–2 and described in detail in the follow-
ing sections.
Table 15–2.Conversion-Modes Summary
CONVERSION MODE CONSEQ OPERATION
Single channel 00 Single conversion from a selected channel
X = CstartAdd, points to the conversion start address
Result is in ADC12MEMx; interrupt flag is ADC12IFG.x
Channel (INCH) and reference voltage (Sref) are selected in ADC12MCTLx
Sequence-of-channels 01 A sequence-of-channels is converted
x = CstartAdd; points to the conversion start address
The last channel in a sequence (y) is marked with EOS=1 (ADC12MCTLx.7), all
other EOS bits in ADC12MCTLx, ADC12MCTL(x+1)..., ADC12MCTL(y–1) are
reset.
Result is in ADC12MEMx, ADC12MEM(x+1),
…
, ADC12MEMy
Interrupt flags are ADC12IFG.x, ADC12IFG.(x+1),
…
, ADC12IFG.y
More than one sequence is possible
Channel (INCH) and reference voltage (Sref) are selected in ADC12MCTLx
Repeat single channel 10 The conversion of one single channel is permanently repeated until repeat is off or
ENC is reset
x = CstartAdd; points to the conversion start address
Result is in ADC12MEMx; interrupt flag is ADC12IFG.x
Channel (INCH) and reference voltage (Sref) are selected in ADC12MCTLx
Repeat sequence-of-
channels 11 The conversion of a sequence-of-channels is permanently repeated until repeat is
off or ENC is reset
x = CstartAdd; points to the conversion start address
The last channel in a sequence (y) is marked with EOS=1 (ADC12MCTL.7), all
other EOS bits in ADC12MCTLx, ADC12MCTL(x+1),
… , ADC12MCTL(y–1) are
reset
Result is in ADC12MEMx, ADC12MEMx+1, … .; interrupt flag is ADC12IFG.x,
ADC12IFG.x+1,
…
.
More than one sequence is possible
Channel (INCH) and reference voltage (Sref) are selected in ADC12MCTLx
15.5.1 Single-Channel, Single-Conversion Mode
The single-channel mode converts a single channel once. The channel to be
converted is selected by the INCH bits in the conversion-memory control regis-
ter (ADC12MCTLx) associated with the conversion-memory register pointed
to by the CStartAdd bits (located in ADC12CTL1x. The conversion range (V
R+
,