Murata DNT24 Series, Руководство по интеграции

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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 DNT24 to settle following a
wake up 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 channels.
The default is the ADC_EXT_REF input. If DAC operation is not needed, setting this parameter to 0x03 will disa-
ble 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 DNT24
has been integrated with the customer’s hardware in some applications. For analog calibration support, contact
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.
5. 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 DNT24. This parameter is used to prevent a router device from clogging up its outbound
queue with its own pending transmissions if it has having trouble obtaining link or an available slot from its parent.
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.
©2009-2014 by Murata Electronics N.A., Inc.
DNT24 Integration Guide R2.0 - 10/27/14
www.murata.com