TMP91C824
91C824-186
③
Channel Fixed Repeat Conversion Mode
Setting ADMOD0<REPET> and ADMOD0<SCAN> to “10” selects Channel Fixed Repeat
Conversion Mode.
In this mode, data on one specified channel is converted repeatedly. When conversion has been
completed, ADMOD0<EOCF> is set to “1” and ADMOD0<ADBF> is not cleared to “0” but held
“1”. INTAD interrupt request generation timing is determined by the setting of ADMOD0<ITM0>.
Setting <ITM0> to “0” generates an interrupt request every time an A/D conversion is completed.
Setting <ITM0> to “1” generates an interrupt request on completion of every fourth conversion.
④
Channel Scan Repeat Conversion Mode
Setting ADMOD0<REPET> and ADMOD0<SCAN> to “11” selects Channel Scan Repeat
Conversion Mode.
In this mode, data on the specified scan channels is converted repeatedly. When each scan
conversion has been completed, ADMOD0<EOCF> is set to “1” and an INTAD interrupt request is
generated. ADMOD0<ADBF> is not cleared to “0” but held “1”.
To stop conversion in a repeat conversion mode (i.e. in cases
③
and
④
), write a “0” to
ADMOD0<REPET>. After the current conversion has been completed, the repeat conversion mode
terminates and ADMOD0<ADBF> is cleared to “0”.
Switching to a halt state (IDLE2 Mode with ADMOD1<I2AD> cleared to “0”, IDLE1 Mode or
STOP Mode) immediately stops operation of the A/D converter even when A/D conversion is still
in progress. In repeat conversion modes (i.e. in cases
③
and
④
), when the halt is released,
conversion restarts from the beginning. In single conversion modes (i.e. in cases
①
and
②
),
conversion does not restart when the halt is released (the converter remains stopped).
Table 3.11.2 shows the relationship between the A/D conversion modes and interrupt requests .
Table 3.11.2 Relationship between A/D Conversion modes and Interrupt requests
ADMOD0
Mode
Interrupt Request
Generation
<ITM0> <REPEAT> <SCAN>
Channel Fixed Single
Conversion Mode
After completion of
conversion
X 0 0
Channel Scan Single
Conversion Mode
After completion of scan
conversion
X 0 1
Every conversion
0
Channel Fixed Repeat
Conversion Mode
Every forth conversion
1
1 0
Channel Scan Repeat
Conversion Mode
After completion of every
scan conversion
X 1 1
X: Don’t care