PIC16F87710-bit 8-channelAnalog-to-Digital Converter

Successive Approximation Algorithm

Thomas L. FloydDigital Fundamentals, 8e

Copyright ©2003 by Pearson Education, Inc.Upper Saddle River, New Jersey 07458

All rights reserved.

PIC16F877 ADC Characteristics

• 10-bit resolution• 8 channel selection by multiplexing• Successive approximation algorithm• Interrupt option• 0V minimum voltage, 5V maximum voltage• Reference voltage selection

ADC Block Diagram

ADCON0 Register

ADCON1 Register

ADC Conversion Steps FlowchartStart

ConfigureI/O Pins

ConfigureADCON1

ConfigureADCON0

Wait AcquisitionTime

Initiate A/DConversion

Read ADCON0GO/DONE

=0?

Read Result

End

Yes

No

20µsec delay

Set GO/DONE biton ADCON0

ADCON1 (BANK 1)Analog pins, Reference voltage,Justification

ADCON0 (BANK 0)Clock speed, Channel Select,Enable ADC

TRISA, TRISE(BANK 1)

ADRESH:ADRESL (BANK 0:BANK 1)

MikroC for PIC ADC Function

unsigned int adc_rd;

void main() { TRISA = 0x02; // Set RA1 pin as input while (1) { adc_rd = ADC_Read(1);// gets ADC value from channel 1 }}

MikroE EasyPic7 Development Board