CHAPTER 11 A/D CONVERTER
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User’s Manual U15195EJ5V0UD
11.8.2 Operation in scan mode
Pins from the conversion start analog input pin to the conversion termination analog input pin specified by the
ADSCM00 or ADSCM10 register are sequentially selected and A/D converted. The A/D conversion result is stored in
the ADCR0m or ADCR1n register corresponding to the analog input (m = 0 to 5, n = 0 to 7). When conversion ends
for all analog inputs up to the conversion termination analog input pin, the A/D conversion end interrupt (INTAD0,
INTAD1) is generated. A/D conversion repeats until the ADCE0 or ADCE1 bit = 0 (ADCS0, ADCS1 bit = 1).
Analog Input
A/D Conversion Result Register
ANIx
Note 1
ADCRx
|
|
ANIx
Note 2
ADCRx
Notes 1.
Set using the SANI3 to SANI0 bits of the ADSCM00 or ADSCM10 register.
Be sure to set a pin number that is smaller than the conversion termination analog input pin number
set according to Note 2.
2.
Set using the ANIS3 to ANIS0 of the ADSCM00 or ADSCM10 register.
Remark
x = 00 to 05, 10 to 17
It is not necessary to write 1 in the ADCE0 or ADCE1 bit of the ADSCM00 or ADSCM10 register as an A/D
conversion restart operation in A/D trigger polling mode
Note
.
This is optimal for applications that regularly read A/D conversion values.
Note
In A/D trigger polling mode, the fact that the ADCE0 or ADCE1 bit of the ADSCM00 or ADSCM10 register
is 0 means that A/D conversion operation does not stop as long as the ADCS0 or ADCS1 bit is not 0.
Therefore, if the ADCR0m or ADCR1n register is not read before the next A/D conversion, it is overwritten.
Figure 11-9. Example of Scan Mode (A/D Trigger Polling Scan) Operation (ANI02 to ANI05):
For A/D Converter 0
ANI00
ANI01
ANI02
ANI03
ANI04
ANI05
ADCR00
ADCR01
ADCR02
ADCR03
ADCR04
ADCR05
A/D converter 0
ADSCM00
(1) ADCE0 bit of ADSCM00 = 1 (Enabled)
(2) A/D conversion of ANI02
(3) Store conversion result in ADCR02
(4) A/D conversion of ANI03
(5) Store conversion result in ADCR03
(6) A/D conversion of ANI04
(7) Store conversion result in ADCR04
(8) A/D conversion of ANI05
(9) Store conversion result in ADCR05
(10) Generate INTAD0 interrupt
(11) Return to (2)