3 comparator_a control registers – Texas Instruments MSP430x1xx User Manual
Page 272
Comparator_A Control Registers
14-6
14.3 Comparator_A Control Registers
The Comparator_A module is configured with three module registers as
shown in Table 14–1. The module registers are mapped into the lower periph-
eral file address range where all byte modules are located and should be ac-
cessed with byte instructions (suffix B).
Table 14–1.Comparator_A Control Registers
Register
Short
Form
Register Type
Address
Initial
State
•
C_A control register 1:
CACTL1
Read/write
059h
Reset
•
C_A control register 2:
CACTL2
Read/write
05Ah
Reset
•
C_A port dissipation reg:
CAPD
Read/write
05Bh
Reset
14.3.1 Comparator_A, Control Register CACTL1
The control register CACTL1 is shown and described below.
CAEX
7
rw-(0)
CA
RSEL
rw-(0)
CA
REF1
rw-(0)
CA
REF0
rw-(0)
CAON
rw-(0)
CAIES
rw-(0)
CAIE
rw-(0)
CAIFG
0
rw-(0)
CACTL1
059h
CAIFG, bit0:
The Comparator_A interrupt flag
CAIE, bit1:
The Comparator_A interrupt enable
CAIES, bit2:
The Comparator_A interrupt edge select bit
0:
The rising edge of the comparator output sets the
Comparator_A interrupt flag CAIFG
1:
The falling edge of the comparator output sets the
Comparator_A interrupt flag CAIFG
CAON, bit3:
The comparator is switched on or off. When off, the cur-
rent consumption of the comparator is stopped. The cur-
rent consumption of the reference circuitry is enabled or
disabled independently.
0:
The comparator is disabled, current consumption is
stopped and the output of the comparator is low.
1:
The comparator is enabled and active.
CAREF, bit4,5:
0:
Internal reference is switched off. An external
reference can be applied.
1:
0.25*Vcc reference is selected
2:
0.50*Vcc reference is selected
3:
Diode reference is selected.
The diode reference varies with each individual
device, temperature and supply voltage. See device
data sheet.