EM77950 datasheet(82/102 Pages) EMC

82 / 102 page

EM77950

BB Controller

•

Product Specification (V1.0) 10.09.2007

(This specification is subject to change without further notice)

ADIE (Bit 6)

: ADC interrupt enable.

ADRUN (Bit 7)

: ADC starts to RUN

= reset on completion of the conversion; this bit cannot be reset by

software.

= an A/D conversion is started; this bit can be set by software.

10.2

Programming Steps/Considerations

Follow these steps to obtain data from the ADC:

Set ADC function power on (PRIE.ADE).

Write to the three bits (IMS2:IMS0) on the ADCCR register to define the

characteristics of PD and PF: Digital I/O, analog channels, and voltage reference

pin;

Write to the ADCAIS register to configure ADC module:

Select ADC input channel (AIPS3: AIPS0)

Define ADC conversion clock rate (CKR2: CKR1: CKR0)

Set ADC interrupt enable (ADCCR.ADIE). Include the “ENI” instruction, if the

interrupt function is employed.

Set the ADRUN bit to 1 to begin sampling.

Wait for either the interrupt flag to be set or the ADC interrupt to occur.

Read the conversion data register ADDATA.

Clear the interrupt flag bit (INTF.ADIF).

For next conversion, go to Step 2 or Step 3 as required. At least 2Tct is required

before the next acquisition starts.

NOTE

To obtain an accurate value, it is necessary to avoid any data transition on the I/O

pins during AD conversion.

EM77950 Datasheet(PDF) 82 Page - ELAN Microelectronics Corp