Hi Brian,

I've done some more reading but no light shed I'm afraid. Here is the setup:

Code:
        CMCON = 3         	' Comparators disabled.
        OSCCON = %01100000  ' Internal 4Mhz.
'        OSCCON = %01110000  ' Internal 8Mhz.
        SSPCON1 = 0              ' Disable serial and configure PortC as I/O.
        ADCON0 = %00000001  ' Enable ADC.
        ADCON1 = %00001100  ' AN0,1,2 the rest Dig, use Vdd for Vref.
        ADCON2 = %10000111  ' Right justify, Frc.
        TRISC = %10011000
The spec sheet for the F877 matches that of the F4620 as far as PortC goes so I don't know why there is a problem with C.3

Any suggestions anyone?

Kind regards,
Bill