Analog to Digital (ADC) Example

Supported Platforms

MODM7AE70, SBE70LC

Overview

The Simple ADC example implements basic analog input functions of the MODM7AE70 and SBE70LC platforms.

The MODM7AE70 offers two Analog Front-End Controllers (AFEC) that are based on an Analog Front-End (AFE) cell. The MODM7AE70 provides seven 12-bit Analog-to-Digital (ADC) lines available through the P2 header. The SBE70LC provides 8 12-bit ADC lines available between the JP1 and JP3 headers. Both platforms have one additional ADC line that is connected to the CPU's internal temperature sensor – it cannot be reconfigured for other applications.

Voltage Reference

An ADC voltage reference is required for accurate ADC readings.

Platform	Reference Pin	Development Board Notes
MODM7AE70	P2[5]	Apply jumper to JP5 on MOD-DEV-70 for 3.3V reference
SBE70LC	JP3[1]	–

MODM7AE70 ADC Pin Mapping

The following table maps the available ADC lines on the MODM7AE70 to the corresponding pins on the P2 header:

Pin	AFE Module	ADC Channel
P2[3]	0	10
P2[6]	1	3
P2[7]	0	0
P2[8]	0	6
P2[21]	0	1
P2[29]	0	5
P2[38]	0	2
*Temp	0	11

Temperature sensor internal to the CPU, not available through the pin header

Important Note

AFE module 0, channel 10 (P2[3]) collides with serial port 0 receive. If using this ADC channel (like this example does), the application will not be able to receive data on serial port 0. It can still print to serial port 0, though.

SBE70LC ADC Pin Mapping

The following table maps the available ADC lines on the SBE70LC to the corresponding pins on the JP1 and JP3 headers:

Pin	AFE Module	ADC Channel
JP1[5]	0	2
JP1[10]	1	0
JP1[11]	0	10
JP1[13]	0	1
JP1[14]	0	5
JP3[3]	1	3
JP3[5]	0	0
JP3[7]	0	6
*Temp	0	11

Temperature sensor internal to the CPU, not available through the pin header