CHAPTER 12 A/D CONVERTER
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User’s Manual U14359EJ4V0UM
(2) 4-buffer mode (external trigger select: 4 buffers)
In this mode, one analog input is A/D converted four times using the ADTRG signal as a trigger and the
results are stored in the ADCR0 to ADCR3 registers. The A/D conversion end interrupt (INTAD) is generated
and A/D conversion is stopped after the 4th A/D conversion.
Trigger
Analog Input
A/D Conversion Result Register
ADTRG signal
ANIn
ADCR0
ADTRG signal
ANIn
ADCR1
ADTRG signal
ANIn
ADCR2
ADTRG signal
ANIn
ADCR3
While the ADCE bit of the ADM0 register is 1, A/D conversion is repeated every time a trigger is input from
the ADTRG pin.
This mode is suitable for applications in which calculate the average of A/D conversion result is calculated.
Figure 12-16. Example of 4-Buffer Mode Operation (External Trigger Select: 4 Buffers)
ANI0
ANI1
ANI2
ANI3
ADCR0
ADCR1
ADCR2
ADCR3
ADCR4
ADCR5
ADCR6
ADCR7
A/D converter
(
×
4)
(
×
4)
ADTRG
(1)
The ADCE bit of ADM0 is set to 1 (enable)
(8)
The external trigger is generated
(2)
The external trigger is generated
(9)
ANI2 is A/D converted
(3)
ANI2 is A/D converted
(10) The conversion result is stored in ADCR2
(4)
The conversion result is stored in ADCR0
(11) The external trigger is generated
(5)
The external trigger is generated
(12) ANI2 is A/D converted
(6)
ANI2 is A/D converted
(13) The conversion result is stored in ADCR3
(7)
The conversion result is stored in ADCR1
(14) The INTAD interrupt is generated