Renesas R8C/20 User Manual

R8C/20 Group, R8C/21 Group 18. A/D Converter
Rev.2.00 Aug 27, 2008 Page 361 of 458
REJ09B0250-0200
Figure 18.1 Block Diagram of A/D Converter
Comparator
AVSS
Data bus
øAD
Resistor ladder
VCUT = 0
VCUT = 1
VREF
Successive conversion register
AD register
ADCON0
Vcom
VIN
P1_0/AN8
CH2 to CH0 = 100b
P1_1/AN9
CH2 to CH0 = 101b
P1_2/AN10
CH2 to CH0 = 110b
P1_3/AN11
CH2 to CH0 = 111b
ADGSEL0 = 1
CH0 to CH2, ADGSEL, CKS0: Bits in ADCON0 register
CKS1, VCUT: Bits in ADCON1 register
A/D conversion rate selection
ADGSEL0 = 0
ADCAP = 1
Software trigger
Timer RD
interrupt request
ADCAP = 0
Trigger
P0_7/AN0
CH2 to CH0 = 000b
P0_6/AN1
CH2 to CH0 = 001b
P0_5/AN2
CH2 to CH0 = 010b
P0_4/AN3
CH2 to CH0 = 011b
P0_3/AN4
CH2 to CH0 = 100b
P0_2/AN5
CH2 to CH0 = 101b
P0_1/AN6
CH2 to CH0 = 110b
P0_0/AN7
CH2 to CH0 = 111b
Decoder
CKS0 = 1
CKS1 = 1
CKS1 = 0
CKS0 = 0
f2
f4
CKS0 = 0
fOCO-F
f1
CKS0 = 1

Renesas R8C/20 Specifications

General

Brand	Renesas
Model	R8C/20
Category	Control Unit
Language	English