Comparator Reference Voltage Select Register (Cmpsel1) - Renesas RX100 Series User Manual

RX13T Group
28.2.3

Comparator Reference Voltage Select Register (CMPSEL1)

Address(es): CMPC0.CMPSEL1 000A 0C88h, CMPC1.CMPSEL1 000A 0CA8h, CMPC2.CMPSEL1 000A 0CC8h
b7 b6
— —
0 0
Value after reset:
Bit Symbol
b1, b0 CVRS[1:0]
b7 to b2 —
Note 1. When the on-chip D/A converter output voltage is used, set the D/A converter for generating comparator C reference voltage
before enabling comparator operation (CMPCTL.HCMPON bit = 1). For details on setting the D/A converter, refer to section 27,
D/A Converter for Generating Comparator C Reference Voltage (DA).
Note 2. Rewrite the CVRS[1:0] bits in the following procedure. Be sure to set the CVRS[1:0] bits to 00b before changing the set value.
Direct rewriting from 01b to 10b or 10b to 01b, for example, will be ignored even if it is tried.
(1) Set the CMPCTL.COE bit to 0.
(2) Set the CVRS[1:0] bits to 00b.
(3) Set a new value to the CVRS[1:0] bits (with 1 set in only one of the bits).
(4) Wait for the stabilization time for input selection. As for the value, refer to section 32, Electrical Characteristics.
(5) Set the CMPCTL.COE bit to 1.
(6) Set the corresponding interrupt status flag (IR) in the interrupt request register to 0.
R01UH0822EJ0100 Rev.1.00
Jul 31, 2019
b5 b4 b3 b2
— — — —
0 0 0 0
Bit Name
Reference Input Voltage Select
1, 2
* *
Reserved
b1 b0
CVRS[1:0]
0 0
Description
b1 b0
0 0: No input
0 1: Input voltage to the CVREFC0 pin selected as reference
input voltage
1 0: On-chip D/A converter 0 output voltage selected as
reference input voltage
Settings other than above are prohibited.
These bits are read as 0. The write value should be 0.
28. Comparator C (CMPC)
R/W
R/W
R/W
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