C8051F93X Datasheet, PDF (96/330 Pages) Silicon Laboratories – Pipelined intstruction architecture executes 70 of instruction in 1 or 2 system clocks

C8051F93x-C8051F92x
7.5. Comparator Register Descriptions
The SFRs used to enable and configure the comparators are described in the following register
descriptions. A Comparator must be enabled by setting the CPnEN bit to logic 1 before it can be used.
From an enabled state, a comparator can be disabled and placed in a low power state by clearing the
CPnEN bit to logic 0.
Important Note About Comparator Settings: False rising and falling edges can be detected by the
Comparator while powering 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. The Comparator Power Up
Time is specified in Section “Table 4.13. Comparator Electrical Characteristics” on page 64.
SFR Definition 7.1. CPT0CN: Comparator 0 Control
Bit
7
6
5
4
3
2
1
0
Name CP0EN CP0OUT CP0RIF CP0FIF
CP0HYP[1:0]
CP0HYN[1:0]
Type R/W
R
R/W
R/W
R/W
R/W
Reset
0
0
0
0
0
0
0
0
SFR Page= 0x0; SFR Address = 0x9B
Bit Name
Function
7
CP0EN Comparator0 Enable Bit.
0: Comparator0 Disabled.
1: Comparator0 Enabled.
6
CP0OUT Comparator0 Output State Flag.
0: Voltage on CP0+ < CP0–.
1: Voltage on CP0+ > CP0–.
5
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.
4
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.
3-2 CP0HYP[1:0] Comparator0 Positive Hysteresis Control Bits.
00: Positive Hysteresis Disabled.
01: Positive Hysteresis = 5 mV.
10: Positive Hysteresis = 10 mV.
11: Positive Hysteresis = 20 mV.
1-0 CP0HYN[1:0] Comparator0 Negative Hysteresis Control Bits.
00: Negative Hysteresis Disabled.
01: Negative Hysteresis = 5 mV.
10: Negative Hysteresis = 10 mV.
11: Negative Hysteresis = 20 mV.
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Rev. 1.3