ctsd16_ex2_singleChSingleConvPolling.c

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//******************************************************************************
//  MSP430FG662x Demo - CTSD16, Single Conversion on a Single Channel, Poll IFG
//
//  Description: This program uses the CTSD16 module to perform a single
//  conversion on a single channel. The CTSD16 interrupt flag for CH0 is polled
//  to determine when a conversion has completed.
//
//  Test by applying a voltage to the input channel and setting a breakpoint
//  at the indicated line. Run program until it reaches the breakpoint, then use
//  the debugger's watch window to view the conversion results.
//
//  Results (upper 16 bits only) are stored in the variable "results"
//
//  ACLK = 32kHz, MCLK = SMCLK = Calibrated DCO = 16.384MHz, SD_CLK = 1.024MHz
//  * Ensure low_level_init.c is included when building/running this example *
//
//  Notes: For minimum Vcc required for CTSD16 module - see datasheet
//         1nF cap btw Vref and AVss is recommended when using 1.2V ref
//
//               MSP430FG662x
//             -----------------
//         /|\|                |
//          | |                |
//          --|RST             |
//            |                |
//   Vin1+ -->|P6.4/A0.0+ VREF |---+
//   Vin1- -->|P6.5/A0.0-      |   |
//            |                |  -+- 1nF
//            |                |  -+-
//            |                |   |
//            |           AVss |---+
//
//
//******************************************************************************
#include "inc/hw_memmap.h"
#include "wdt_a.h"
#include "gpio.h"
#include "ctsd16.h"
 
uint32_t  results;                          // CTSD16 Conversion Results
 
void main(void) {
    // Stop WDT
    WDT_A_hold(WDT_A_BASE);
 
    // Select AD0+/- analog input pins
    GPIO_setAsPeripheralModuleFunctionInputPin(GPIO_PORT_P6, GPIO_PIN4 | GPIO_PIN5);
 
    // Initialize CTSD16 using internal reference and internal resistor for clock
    CTSD16_init(CTSD16_BASE,
            CTSD16_RTR_INPUT_CHARGEPUMP_BURST_REQUEST_DISABLE, CTSD16_REF_INTERNAL);
 
    // Initialize converter 0: AD0+ / AD0- as input, channel 9
    CTSD16_initConverter(CTSD16_BASE, CTSD16_CONVERTER_0, CTSD16_SINGLE_MODE, 
        CTSD16_INPUT_CH9);
 
    // Delay ~120us for 1.2V ref to settle
    __delay_cycles(2000);
 
    while(1) {
         // Set bit to start conversion
        CTSD16_startConverterConversion(CTSD16_BASE, CTSD16_CONVERTER_0);
        // Poll IFG until conversion completes
        while(!CTSD16_getInterruptStatus(CTSD16_BASE, CTSD16_CONVERTER_0, CTSD16_CONVERTER_INTERRUPT));
        // Save CTSD16 conversion results
        results = CTSD16_getResults(CTSD16_BASE, CTSD16_CONVERTER_0);
        __no_operation();                       // SET BREAKPOINT HERE
    }
}