A/D how to add two channels (CHS2 and CHS1 or CHS0)?

[desire608]

Anyone knows how to add two channels (CHS2 and CHS1 or CHS0)?
Using PIC18f1220
I have connected one input to AN4/RB0 pin(8) using CHS2 (bit 010) which is working good, but I want to add another input e.g. on AN5/RB1 pin(9).I have study the datasheet and have tried but unfortunately couldn’t able to do.
Any idea or can do for me please.

what I have done A/D code

ADCON1 =0x6F; //all IO are digital or 0b01101111 in binary on PORT A
TRISA = 0b00100000; //sets PORTA
PORTA = 0b00000000; //turns off PORTA outputs
TRISB = 0b01000001; //sets PORTB as all outputs
PORTB = 0b00000000; //turns off PORTB outputs, good start position
ADCON0bits.CHS2=1; //read port RB0
ADCON0bits.ADON = 1; //turn on A/D
ADCON2 = 0b10000000; //right justified, acquisition times are ok at 0 with 31kHz on PORT B
while (1)
{
ADCON0bits.GO = 1;

king regrads

 

[Ian Rogers]

ADCON1 = 01101111 ; // selects AN4.
//To use AN5 & AN4  (example)
ADCON1 = 01001111 ; // selects both.

ACCON0 = 0;
ADCON0bits.CHS2 =1  ); // AN4
ADCON0 += 1; // switch on
ACDON0bits. GO = 1;

// Then
ACCON0 = 0;
ADCON0bits.CHS2 =1  ); 
ADCON0bits.CHS0 =1  ); // AN5
ADCON0 += 1; // switch on
ACDON0bits. GO = 1;

If you are using C18.. its far easier to use thier ADC library.
*NOTE* there needs to be a little time ,(a couple of uS), between ADCONbits.ON and ADCONbits.GO.

 

[be80be]

You need to set your TRISB to input on AN4 and AN5 and you can't read them both at the same time Read AN4 delayUS read AN5

ADCON1 = 0x4F; Like Ian said and it should work if you delay a few us between reading and save them as there done reading the pins.

TRISB = 0b01000011;

 

[desire608]

Dear Ian Rogers and be80be

Thank you very much indeed. I have put the delay between both channels and its working
Once again thank you

Kind regards