Hello Forum,

I've been trying but without success to kickstart the ADC10 on a 
MSP430F1222.

I can't seem to get ADC10 to work. I simply want to measure 
temperature and Vcc/2 using on-board peripherals. No external analog 
signals. I want to use the Internal reference too.

I seem to be communicating with my FET okay. But setting break-points 
and 'watching' ADC10 registers shows that what I want the MCU to do 
isn't happenning. The ADC10 registers nor flags are being updated and 
I don't get an interrupt (to confirm end of conversion).

In the background, my uC keeps a RTC, driven from a watch crystal, 
ACLK, (i.e. WDT - runs in Interwal Mode. That works okay and the WDT 
DOES generate Interrupts.). 

I hope to use the faster, DCO for main processing, which 
theoretically should result in overall low-power consumption.


About the ADC10:

I'm a bit unclear about the order of setting up the ADC10CTL0 and 
ADC10CTL1 registers and bits inside them. I haven't even got round to 
Data Transfer Control Registers yet...

Has anyone tried the TI 'C' sample codes, successfully? with this 
part (MSP430F1222 or  1232). Did you have to make any changes to get 
the code to work? 

MSP430F1xxx user guide, Chapter10.ADC10, Figure 16-4 shows 'Single 
Channel, Single Conversion Mode' sequence, which appears straight 
forward enough, but what about initialisation prior to it. I.e. REFON 
bit is apparently set automatically if INCHx
h and ENC bit must be 
RESET before writing to 'CTLx registers...

Using the following sample code (fet120_adc10_temp.c) I seem to never 
wake up from SLEEP (even though my GIE and ADC10IE are believed to be 
set).

.
.
init_clock();  // XT1=LK and DCO 
               // when FET disconnected both these clock can be 
seen           //at the appropriate ports ACLCK and SMCLK

init_wdt();   // 1s Interval Mode
.
.
.

      
                              // Get Temperature

  ADC10CTL1 = INCH_10+ADC10DIV_3;  // Temp Sensor ADC10CLK/4   
  ADC10CTL0 = SREF_1 + ADC10SHT_3 + REFON + ADC10ON + ADC10IE;
  
    for (delay=0; delay ; delay++);

  while(1)
  {
    P2OUT |= SPAREIO;            // TOGGLE TEST PIN

    ADC10CTL0 |= ENC + ADC10SC;  // Sampling and conversion start
    _BIS_SR(CPUOFF + GIE);       // LPM0 with interrupts enabled
  
//  oF = ((A10/1024)*1500mV)-923mV)*1/1.97mV = x*761/1024 - 468 
    temp = ADC10MEM;
    IntDegF = ((temp - 630) * 761) / 1024;         

//  oC = ((A10/1024)*1500mV)-986mV)*1/3.55mV = x*423/1024 - 278 
    temp = ADC10MEM;
    IntDegC = ((temp - 673) * 423) / 1024;         
    
    P2OUT &= ~SPAREIO;                   // 
  
    

    _NOP();                             // SET BREAKPOINT HERE

  }
.
.
.
.
}


Here is the ISR...



// ADC10 interrupt service routine
void ADC10_ISR (void) __interrupt[ADC10_VECTOR] 
{
    _BIC_SR_IRQ(CPUOFF);                // Clear CPUOFF bit from 0(SR)
}



Can anyone see what is wrong with this code or point me in the right 
direction please.


Thanks,

PaulW.