mpy32_ex14_saturationOverflow.c

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//******************************************************************************
//******************************************************************************
#include "driverlib.h"
 
uint32_t Result;
uint16_t Result_lower16;
uint16_t Result_upper16;
 
void main (void)
{
    //Stop Watchdog Timer
    WDT_A_hold(WDT_A_BASE);
 
//------Pre-Multiply to setup RES0 and RES1 ------------------------
 
    MPY32_setOperandOne16Bit(
        MPY32_MULTIPLY_UNSIGNED,
        0xFFFF);
    MPY32_setOperandTwo16Bit(
        0x8000);
    MPY32_setOperandOne16Bit(
        MPY32_MULTIPLYACCUMULATE_UNSIGNED,
        0x7FFD);
    MPY32_setOperandTwo16Bit(
        0x1);
 
//------32-bit Result of a multiply operation in RES0 and RES1------
//RES1 == 0x7FFF
//RES0 == 0xFFFD
 
    //Enable Saturation Mode
    MPY32_enableSaturationMode();
 
    //Set a 16-bit Operand into the specific Operand 1 register to specify
    //signed multiplication added to the current result
    MPY32_setOperandOne16Bit(
        MPY32_MULTIPLYACCUMULATE_SIGNED,
        0x05);
 
    //Set 16-bit Operand 2 to begin the multiplication operation
    MPY32_setOperandTwo16Bit(
        0x01);
 
    //Wait for the result to become ready
    __no_operation();
    __no_operation();
    __no_operation();
    __no_operation();
    __no_operation();
 
    //Read out Result
    Result = MPY32_getResult();
 
    Result_upper16 = Result;
    Result_lower16 = (Result >> 16);
 
    //Disable Saturation Mode
    MPY32_disableSaturationMode();
 
    //Enter LPM4
    __bis_SR_register(LPM4_bits);
 
    //BREAKPOINT HERE to verify the correct Results:
    //Result_upper16 == 0x7FFF
    //Result_lower16 == 0xFFFF
    __no_operation();
}