TMP92CF30
2009-06-12
92CF30-529
3.22.2.3 Starting an AD Conversion
The AD conversion has the two types of normal AD conversion and top-priority AD
conversion.
Normal AD conversion can be started up by setting ADMOD0<ADS> to “1.”
Top-priority AD conversion can be started up by software by setting
ADMOD2<HADS> to “1.”
For normal AD conversion, one operation mode is selected from the four types of
operation modes specified by ADMOD1<REPEAT, SCAN>. The operation mode for
top-priority AD conversion is only single conversion by channel-fix mode.
The ADC supports two types of AD conversion: normal AD conversion and
Top-priority AD conversion. The ADC initiates a normal AD conversion by software
when the ADMOD0<ADS> is set to “1”. It initiates a Top-priority AD conversion by
software when the ADMOD2<HADS> is set to “1”. For a normal AD conversion,
ADMOD1<REPEAT, SCAN> select one of four conversion modes. For a Top-priority
AD conversion, the ADC only supports Fixed-Channel Single Conversion mode.
The ADMOD0<TSEL1:0> and ADMOD2<HTSEL1:0> enable a hardware trigger for
a normal and Top-priority AD conversion, respectively. When these bits are set to “10”,
a normal or Top-priority AD conversion is triggered by a falling edge applied to
ADTRG
pin. When ADMOD0<TSEL1:0> is set to “00”, a normal AD conversion is triggered by
INTTB00 of 16-Bit Timer interrupt. When ADMOD2<HTSEL1:0> is set to “00”, a
Top-priority AD conversion is triggered by INTTB10 of 16-Bit Timer interrupt. If this
bit is “11”, it is triggered by I
2
S sampling block. Even when a hardware trigger is
enabled, software starting can be used.
Note: If changing HTSEL at HHTRGE is “ON”, maybe unexpected interrupts occurs. If changing HTSEL, once set
HHTRGE to “OFF”.
When normal AD conversion is started, the AD conversion BUSY flag
(ADMOD0<BUSY>) that shows the state for AD being converted is set to “1.”
When top-priority AD conversion is started, the AD conversion BUSY flag
(ADMOD2<HBUSY>) that shows the state for AD being converted is set to “1.”
In addition, when top-priority conversion is started during normal AD conversion,
ADMOD0<BUSY> is kept to “1.”
Summary of Contents for TLCS-900/H1 Series
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