Tutorial on Analog to Digital / LPC214x

Reference : Document UM10139 Chapter 19

Purpose:
To learn, How to enable & use the inbuilt ADC module of LPC21xx ??? Display the current digital value of analog signal on channel 3 of ADC0 onto an alphanumeric LCD.

Notes:

LPC2148 has two inbuilt ADC modules, ADC0 & ADC1.

Each ADC is of 10 bit resolution, using Successive approximation conversion technique.

ADC0 has 6 channels and ADC1 has 8 channels. (14 analog Channels)

Supports maximum clock at 4.5 MHz.

Lots of registers are there associated to ADC, but i am going to tell you only important ones here, any time you can refer UM10139, chapter 19 for more details of ADCs special function registers.

The register we must know about is, ADC Control register (AD0CR or AD1CR) & ADGDR (ADC Global data register)

Go through all the bit description above, see how many opearating modes are there, How to configure the clock to ADC.

Look carefully to bits 6:15 and 31 of ADGDR register. 

 

Code snippet from adc.c