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When the ADC is operating in differential mode, the ADC1 to ADC0 differential measurement is compared to the
“0” high and low thresholds, and the ADC2 to ADC0 differential measurements is compared to the “1” high and
low thresholds. In this case the “2” threshold values are not used.

7. Set the

IoPreDelay

parameter as needed in Bank 6 to allow signals to stabilize following a module wakeup event.

8. Set the

AdcSkipCount

parameter in Bank 6 as needed to allow

internal

transients in the ADC sample-and-hold

circuit to settle out. This parameter must be set to at least 3 when

AdcDiffMode

is selected. Note that the

Io-

PreDelay

parameter discussed above provides a delay to allow signals

external

to the DNT90M to settle following

an event, while

AdcSkipCount

skips measurements that may be distorted because the

internal

voltage on the

ADC sample-and-hold has not settled.

9. Select the DAC full scale reference by setting

DacReference

in Bank 6. This setting applies to both DAC chan-

nels. The default is the ADC_EXT_REF input. If DAC operation is not needed, setting this parameter to 0x03 will
disable DAC operation, reducing current consumption.

10. Configure the initial (power on) output level for DAC0 and DAC1 by loading the initial settings in the

Dac0Init

and

Dac1Init

parameters respectively.

The ADC and DAC channels are factory calibrated. It may be desirable to fine tune these calibrations after the
DNT90M has been integrated with the customer’s hardware in some applications. For analog calibration support, con-
tact Murata technical support.

5.5

Configuring I/O Event Reporting and I/O Binding

1. Select the analog, digital and timing events that will trigger an I/O event report by setting the

respective bits in the

IoReportTrigger

parameter in Bank 6. The default is no triggers set.

2. Configure the trigger behavior bits in the

GpioEdgeTrigger

parameter, Bank 6, for each GPIO

input selected to generate an I/O event report.

3. For each ADC channel selected to generate an I/O event, set the high and low measurement threshold values.

The

AdcThreshold

parameters are in Bank 6. When the ADC is operating in differential mode, the ADC1 to ADC0

differential measurement is compared to the “0” high and low thresholds, and the ADC2 to ADC0 differential
measurements is compared to the “1” high and low thresholds. In this case the “2” threshold values are not used.

4. If the periodic timer has been selected to generate an event report, load the required timer report interval into the

IoReportInterval

parameter in Bank 6. The default timer interval is 30 seconds.

Set the MaxQueuedEvents

parameter in Bank 6 as needed to limit the number of Event Reports that can be

queued at one time by a DNT90M.

6. If I/O binding operation is desired, set the

IoBindingEnable

parameter in Bank 6 to 0x01.

I/O binding is disabled by default, and cannot be used when the ADC is operating in
differential mode.

5.6

Configuring Sleep Mode