
C8051F040/1/2/3/4/5/6/7
102
Rev. 1.5
7.3.2. Window Detector in Differential Mode
Figure 7.6 shows two example window comparisons for differential mode, with ADC2LT = 0x10 (+16d) and
ADC2GT = 0xFF (–1d). Notice that in Differential mode, the codes vary from –VREF to VREF x (127/128)
and are represented as 8-bit 2s complement signed integers. In the left example, an AD2WINT interrupt
will be generated if the ADC2 conversion word (ADC2L) is within the range defined by ADC2GT and
ADC2LT (if 0xFF (–1d) < ADC2 < 0x0F (16d)). In the right example, an AD2WINT interrupt will be gener-
ated if ADC2 is outside of the range defined by ADC2GT and ADC2LT (if ADC2 < 0xFF (–1d) or ADC2 >
0x10 (+16d)).
Figure 7.6. ADC Window Compare Examples, Differential Mode
0x7F (127d)
0x11 (17d)
0x10 (16d)
0x0F (15d)
0x00 (0d)
0xFF (-1d)
0xFE (-2d)
0x80 (-128d)
-REF
Input Voltage
(P1.x - P1.y)
REF x (127/128)
REF x (16/128)
REF x (-1/256)
0x7F (127d)
0x11 (17d)
0x10 (16d)
0x0F (15d)
0x00 (0d)
0xFF (-1d)
0xFE (-2d)
0x80 (-128d)
-REF
Input Voltage
(P1.x - P1.y)
REF x (127/128)
REF x (16/128)
REF x (-1/256)
AD2WINT=1
AD2WINT
not affected
AD2WINT
not affected
ADC2LT
ADC2GT
AD2WINT
not affected
ADC2GT
ADC2LT
AD2WINT=1
ADC2