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c.
Channel fixed repeat conversion mode
Setting ADMOD0<REPEAT> 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
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 AD
conversion is completed.
Setting <ITM0> to 1 generates an interrupt request on completion of every
fourth conversion.
d.
Channel scan repeat conversion mode
Setting ADMOD0<REPEAT> 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 (e.g., in cases c. and d.), write a
0 to ADMOD0<REPEAT>. 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 AD converter
even when AD conversion is still in progress. In repeat conversion modes (e.g., in
cases c. and d.), when the halt is released, conversion restarts from the beginning.
In single conversion modes (e.g., in cases a. and b.), conversion does not restart
when the halt is released (The converter remains stopped).
Table 3.11.2 shows the relationship between the AD conversion modes and
interrupt requests.
Table 3.11.2 Relationship between AD Conversion Modes and Interrupt Requests
Interrupt Request
Mode
Generation
Channel fixed single
After completion of
conversion mode
conversion
Channel scan single
After completion of scan
conversion mode
conversion
Channel fixed repeat
Every conversion
conversion mode
Every forth conversion
Channel scan repeat
After completion of every
conversion mode
scan conversion
X: Don't care
been
completed,
ADMOD0<EOCF>
<ITM0>
X
X
0
1
X
91C824-189
TMP91C824
is
set
ADMOD0
<REPEAT>
<SCAN>
0
0
0
1
1
0
1
1
2008-02-20
to
1
and
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