Fujitsu FR81S User Manual
CHAPTER 44: 12-BIT A/D CONVERTER
5. Operation
FUJITSU SEMICONDUCTOR LIMITED
CHAPTER : 12-BIT A/D CONVERTER
FUJITSU SEMICONDUCTOR CONFIDENTIAL
FUJITSU SEMICONDUCTOR CONFIDENTIAL
99
Range comparison operation
When the range comparison enable setting (ADRCCS.RCOE="1"), the range comparison is executed when
the A/D conversion is completed and data is stored in A/D data bit (ADTCD.D11 to D0). The range
comparison compares the upper and lower bound threshold setting register (ADRCUT/ADRCLT) selected
by the range comparison upper and lower bound threshold selection bit (ADRCCS.RCOTS1,RCOTS0) with
the A/D data bit (ADTCD.D11 to D0). The range comparison result is input to a continuous detecting
function.
the A/D conversion is completed and data is stored in A/D data bit (ADTCD.D11 to D0). The range
comparison compares the upper and lower bound threshold setting register (ADRCUT/ADRCLT) selected
by the range comparison upper and lower bound threshold selection bit (ADRCCS.RCOTS1,RCOTS0) with
the A/D data bit (ADTCD.D11 to D0). The range comparison result is input to a continuous detecting
function.
Table 5-8 Range comparison upper and lower bound threshold select
Range comparison result
Confirmation
outside the range
(ADRCCS:
RCOIRS="0")
Confirmation
inside the range
(ADRCCS:
RCOIRS="1")
Outside the range (larger than upper bound threshold)
A/D data bit
Upper bound threshold setting register
Detection
Undetection
Inside the range
A/D data bit
Upper bound threshold setting register
and
A/D data bit
Lower bound threshold setting register
Undetection
Detection
Outside the range (Smaller than lower bound threshold)
A/D data bit
Lower bound threshold setting register
Detection
Undetection
Figure 5-21 Range comparison condition
→time
Voltage
↑
Outside range
(upper bound
threshold excess)
Range
Outside range
(less than lower
bound threshold)
Upper bound threshold
setting register0
(ADRCUT0)
Lower bound threshold
setting register0
(ADRCLT0)
1.
2.
3.
4.
5.
6.
A/D
conversion
result
Continuous detecting function of range comparison result
A continuous detecting function continuously detects the range comparison result, and removes the noise
etc.
When the count in which the detection of the range comparison result is set by range comparison
continuousness detection count specification setting (ADRCCS.RCOCD2 to RCOCD0) is continuously
detected, "1" is set to range comparison interrupt factor flag bit (ADRCIF.RCINT). When it becomes
undetection even one time in the continuous detection by the range comparison result, the continuous
detection measurement is cleared to 0 times and the measurement is a fresh start.
etc.
When the count in which the detection of the range comparison result is set by range comparison
continuousness detection count specification setting (ADRCCS.RCOCD2 to RCOCD0) is continuously
detected, "1" is set to range comparison interrupt factor flag bit (ADRCIF.RCINT). When it becomes
undetection even one time in the continuous detection by the range comparison result, the continuous
detection measurement is cleared to 0 times and the measurement is a fresh start.
MB91520 Series
MN705-00010-1v0-E
1902