Texas Instruments MSP430x4xx - Manual (Page 417)

SD16 Operation
21-14 SD16
Figure 21−9. Start of Conversion using Preload
Delayed Conversion
40
SD16OSRx = 32
Start of
Conversion
Time
Conversion
32
Conversion
32 f M cycles:
1st Sample Ch1
SD16PRE0 = 8
SD16PRE1 = 0 Conversion
32
Conversion
32
Conversion
32
Conversion
1st Sample Ch0
When channels are grouped, care must be taken when a channel or channels
operate in single conversion mode or are disabled in software while the master
channel remains active. Each time channels in the group are re-enabled and
re-synchronize with the master channel, the preload delay for that channel will
be reintroduced. Figure 21−10 shows the re-synchronization and preload
delays for channels in a group. It is recommended that SD16PREx = 0 for the
master channel to maintain a consistent delay between the master and
remaining channels in the group when they are re-enabled.
Figure 21−10. Preload and Channel Synchronization
Channel 0
SD16SNGL = 0
SD16GRP = 1
Time
Conversion
SD16SC
Channel 1
SD16SNGL = 1
SD16GRP =1
Conversion
Channel 2
SD16SNGL = 0
SD16GRP = 0
Conversion
SD16SC
SD16SC
Conversion Conversion
Set by Ch2 Auto−clear
Set by Ch2
Conv
Set by SW
Conversion
Set by SW Auto−clear
(syncronized to master)
Cleared by SW
Conv
Set by SW
(syncronized to master)
= Result written to SD16MEMx
PRE1 PRE1
PRE0
Conversion
PRE0 Conv