C8051F336_08 Datasheet, PDF (46/227 Pages) Silicon Laboratories – Mixed-Signal Byte-Programmable EPROM MCU

C8051F336/7/8/9
7.3.1. Window Detector In Single-Ended Mode
Figure 7.4 shows two example window comparisons for right-justified, single-ended data, with
ADC0LTH:ADC0LTL = 0x0080 (128d) and ADC0GTH:ADC0GTL = 0x0040 (64d). In single-ended mode,
the input voltage can range from ‘0’ to VREF x (1023/1024) with respect to GND, and is represented by a
10-bit unsigned integer value. In the left example, an AD0WINT interrupt will be generated if the ADC0
conversion word (ADC0H:ADC0L) is within the range defined by ADC0GTH:ADC0GTL and
ADC0LTH:ADC0LTL (if 0x0040 < ADC0H:ADC0L < 0x0080). In the right example, and AD0WINT interrupt
will be generated if the ADC0 conversion word is outside of the range defined by the ADC0GT and
ADC0LT registers (if ADC0H:ADC0L < 0x0040 or ADC0H:ADC0L > 0x0080). Figure 7.5 shows an exam-
ple using left-justified data with the same comparison values.
Input Voltage
(Px.x - GND)
VREF x (1023/
1024)
ADC0H:ADC0L
0x03FF
VREF x (128/1024)
VREF x (64/1024)
0x0081
0x0080
0x007F
0x0041
0x0040
0x003F
AD0WINT
not affected
Input Voltage
(Px.x - GND)
VREF x (1023/
1024)
ADC0H:ADC0L
0x03FF
ADC0LTH:ADC0LTL
AD0WINT=1
ADC0GTH:ADC0GTL
VREF x (128/1024)
VREF x (64/1024)
0x0081
0x0080
0x007F
0x0041
0x0040
0x003F
AD0WINT=1
ADC0GTH:ADC0GTL
AD0WINT
not affected
ADC0LTH:ADC0LTL
0
0x0000
AD0WINT
not affected
0
0x0000
AD0WINT=1
Figure 7.4. ADC Window Compare Example: Right-Justified Single-Ended Data
Input Voltage
(Px.x - GND)
VREF x (1023/
1024)
ADC0H:ADC0L
0xFFC0
VREF x (128/1024)
VREF x (64/1024)
0x2040
0x2000
0x1FC0
0x1040
0x1000
0x0FC0
AD0WINT
not affected
Input Voltage
(Px.x - GND)
VREF x (1023/
1024)
ADC0H:ADC0L
0xFFC0
ADC0LTH:ADC0LTL
AD0WINT=1
ADC0GTH:ADC0GTL
VREF x (128/1024)
VREF x (64/1024)
0x2040
0x2000
0x1FC0
0x1040
0x1000
0x0FC0
AD0WINT=1
ADC0GTH:ADC0GTL
AD0WINT
not affected
ADC0LTH:ADC0LTL
0
0x0000
AD0WINT
not affected
0
0x0000
AD0WINT=1
Figure 7.5. ADC Window Compare Example: Left-Justified Single-Ended Data
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Rev.1.0