HD404459 Datasheet, PDF (99/122 Pages) Renesas Technology Corp – 4-bit HMCS400-series microcomputers

HD404459 Series
Comparator Control Register (CCR: $016): Four-bit write-only register which selects a 16-level internal
reference power supply (figure 80). The comparator control register (CCR: $016) is reset to $0 by MCU
reset.
Comparator control register (CCR: $016)
Bit
Initial value
Read/Write
Bit name
3
0
W
CCR3
2
0
W
CCR2
1
0
W
CCR1
0
0
W
CCR0
CCR3
0
1
CCR2
0
1
0
1
CCR1
0
1
0
1
0
1
0
1
CCR0
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
Reference power supply selection
1/17 V_CC
2/17 V_CC
3/17 V_CC
4/17 V_CC
5/17 V_CC
6/17 V_CC
7/17 V_CC
8/17 V_CC
9/17 V_CC
10/17 V_CC
11/17 V_CC
12/17 V_CC
13/17 V_CC
14/17 V_CC
15/17 V_CC
16/17 V_CC
Figure 80 Comparator Control Register (CCR)
Comparator Enable Register (CER: $017): This register consists of a 3-bit write-only register and a 1-bit
read-only register. It selects the analog input pins and reference voltage, and indicates the voltage
comparison result. The comparison result output is 0 when an analog input voltage is lower than the
reference voltage, and is 1 when an analog input voltage is higher than the reference voltage. The
comparison result is read by the bit test instruction (TM or TMD). The comparator enable register (CER:
$017) is reset to $0 by MCU reset.
97