[avr-gcc-list] anyone work with ADC on 355E?

[ken omura]

hello, i have been trying to get the ADC to read..
i am using some ADC code from a 355 demo... and
i find that it is looping in the while loop below:

void MT_ADStartConv(void)
{
    while (a_dcomp == NOTHING);    // Wait for 1st
conversion to clear
    a_dcomp = CONVERT ;           // Tell the next
routine that conversion is ongoing  
    ADCSR |= BIT(ADSC) ;          // start A/D
conversion
}

the interrupt that changes the value of a_dcomp isn't
being called.
is that because the start A/D conversion bit isn't set
until line #3??
anyone know what this "1st conversion to clear" refers
to?

also, does anyone know what the value of AG_A2D_ADCSR
is in the following?

void AG_Setup_ADC(void)
{
    ADCSR = BIT(ADSC) | AG_A2D_ADCSR;
    ADMUX = CLEAR ;                    // connects to
first pin by clearing A/D's MUX
    a_dcomp = NOTHING ;                // clears out
interrupt first
}

thanks,
ken


        
                
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