C8051F330-GMR Datasheet, PDF (64/210 Pages) Silicon Laboratories – Mixed-Signal ISP Flash MCU

C8051F330/1/2/3/4/5
logic 1 upon a Comparator falling-edge occurrence, and the CP0RIF flag is set to logic 1 upon the Com-
parator rising-edge occurrence. Once set, these bits remain set until cleared by software. The Comparator
rising-edge interrupt mask is enabled by setting CP0RIE to a logic 1. The Comparator0 falling-edge inter-
rupt mask is enabled by setting CP0FIE to a logic 1.
The output state of the Comparator can be obtained at any time by reading the CP0OUT bit. The Compar-
ator is enabled by setting the CP0EN bit to logic 1, and is disabled by clearing this bit to logic 0.
Note that false rising edges and falling edges can be detected when the comparator is first powered on or
if changes are made to the hysteresis or response time control bits. Therefore, it is recommended that the
rising-edge and falling-edge flags be explicitly cleared to logic 0 a short time after the comparator is
enabled or its mode bits have been changed. This Power Up Time is specified in Table 8.1 on page 70.
SFR Definition 8.1. CPT0CN: Comparator0 Control
R/W
CP0EN
Bit7
R
CP0OUT
Bit6
R/W
CP0RIF
Bit5
R/W
CP0FIF
Bit4
R/W
R/W
R/W
R/W
Reset Value
CP0HYP1 CP0HYP0 CP0HYN1 CP0HYN0 00000000
Bit3
Bit2
Bit1
Bit0 SFR Address:
0x9B
Bit7:
Bit6:
Bit5:
Bit4:
Bits3–2:
Bits1–0:
CP0EN: Comparator0 Enable Bit.
0: Comparator0 Disabled.
1: Comparator0 Enabled.
CP0OUT: Comparator0 Output State Flag.
0: Voltage on CP0+ < CP0–.
1: Voltage on CP0+ > CP0–.
CP0RIF: Comparator0 Rising-Edge Flag. Must be cleared by software.
0: No Comparator0 Rising Edge has occurred since this flag was last cleared.
1: Comparator0 Rising Edge has occurred.
CP0FIF: Comparator0 Falling-Edge Flag. Must be cleared by software.
0: No Comparator0 Falling-Edge has occurred since this flag was last cleared.
1: Comparator0 Falling-Edge has occurred.
CP0HYP1–0: Comparator0 Positive Hysteresis Control Bits.
00: Positive Hysteresis Disabled.
01: Positive Hysteresis = 5 mV.
10: Positive Hysteresis = 10 mV.
11: Positive Hysteresis = 20 mV.
CP0HYN1–0: Comparator0 Negative Hysteresis Control Bits.
00: Negative Hysteresis Disabled.
01: Negative Hysteresis = 5 mV.
10: Negative Hysteresis = 10 mV.
11: Negative Hysteresis = 20 mV.
Rev. 1.7
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