TM4C1237D5PM_15 Datasheet, PDF (791/1277 Pages) Texas Instruments – Tiva Microcontroller

Tiva^™ TM4C1237D5PM Microcontroller
13.3.7.3
Function Ranges
The two comparison values, COMP0 and COMP1, in the ADC Digital Comparator Range
(ADCDCCMPn) register effectively break the conversion area into three distinct regions. These
regions are referred to as the low-band (less than COMP0), mid-band (greater than COMP0 but less
than or equal to COMP1), and high-band (greater than or equal to COMP1) regions. COMP0 and COMP1
may be programmed to the same value, effectively creating two regions, but COMP1 must always
be greater than or equal to the value of COMP0. A COMP1 value that is less than COMP0 generates
unpredictable results.
Low-Band Operation
To operate in the low-band region, the CIC field field in the ADCDCCTLn register must be
programmed to 0x0. This setting causes interrupts or triggers to be generated in the low-band region
as defined by the programmed operational mode. An example of the state of the interrupt/trigger
signal in the low-band region for each of the operational modes is shown in Figure 13-12 on page 791.
Note that a "0" in a column following the operational mode name (Always, Once, Hysteresis Always,
and Hysteresis Once) indicates that the interrupt or trigger signal is deasserted and a "1" indicates
that the signal is asserted.
Figure 13-12. Low-Band Operation (CIC=0x0)
COMP1
COMP0
Always – 0 0 0 0 1 1 1 0 0 1 1 0 0 0 0 1
Once – 0 0 0 0 1 0 0 0 0 1 0 0 0 0 0 1
Hysteresis Always – 0 0 0 0 1 1 1 1 1 1 1 1 0 0 0 1
Hysteresis Once – 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 1
Mid-Band Operation
To operate in the mid-band region, the CIC field field in the ADCDCCTLn register must be
programmed to 0x1. This setting causes interrupts or triggers to be generated in the mid-band region
according the operation mode. Only the Always and Once operational modes are available in the
mid-band region. An example of the state of the interrupt/trigger signal in the mid-band region for
each of the allowed operational modes is shown in Figure 13-13 on page 792. Note that a "0" in a
column following the operational mode name (Always or Once) indicates that the interrupt or trigger
signal is deasserted and a "1" indicates that the signal is asserted.
June 12, 2014
791
Texas Instruments-Production Data