Motorola Mobility LLC T56KT1 User Manual

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Chapter 2:  Hardware Interface Description
 December 15, 2009
G30 - Module Hardware Description
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A/D Interface
The G30 includes 3 Analog to Digital Converter (ADC) signals with 12-bit resolution, for 
environmental and electrical measurements. The ADC signals measure an analog DC voltage 
level on their inputs which is converted to a 12-bit digital value for further processing by G30 or 
the user application.
The A/D signals operation and reporting mechanism is defined by the AT+MMAD command. 
Each A/D can be defined to provide several reports:
A single measurement.
A single A/D measurement will take place and will be reported upon activation of the AT 
command.
An automatic periodical measurement.
The A/D measures its input signal at a rate that is defined by the user application. Every 
measurement will generate an unsolicited message over the serial interface.
An automatic periodical measurement with predefined limits.
The A/D measures its input signal at a rate that is defined by the user. The user also defines 
upper and/or lower limits for the A/D measurements. Each measurement is compared to 
these limits, and an unsolicited message is generated only if these limits are exceeded.
Important:
In case the defined periodical measurement rate is equal to, or shorter than, the 
defined sleep mode delay settings (ATS24), G30 will not enter low power mode.
Important:
Applying voltage to ADC lines before power up is forbidden and may cause G30 
power up issues.
Power Supply A/D
The main power supply (VCC) is constantly monitored internally by the G30 through a dedicated 
A/D signal, which is not accessible on the interface connector.
The measured VCC level can be read and monitored by the user application through the 
AT+MMAD command, which returns the measured VCC level in Volts times 100.
For example, a measured supply level of 3.65 Volts will be presented as 365 by the MMAD 
command.