//****************************************************************************** // MSP430G2x12/G2x52 Demo - Comp_A, Detect Threshold, Set P1.0 if P1.1 > 0.25*Vcc // // Description: Use Comparator_A to detect a voltage threshold // Using an external potentiometer, an unknown voltage is applied to P1.1 // Comparator_A compares the unknown voltage to an internal reference // voltage, in this example 0.25*VCC If the unknown voltage is higher // than 0.25*VCC, P1.0 is set, if not, P1.0 is reset // ACLK = n/a, MCLK = SMCLK = default DCO // // MSP430G2x12/G2x52 // // /|\ | XIN|// | | | // -|RST XOUT|// | | | // RLED // | | | // -|VSS // // D Dang // Texas Instruments Inc // December 2010 // Built with CCS Version 4.2.0 and IAR Embedded Workbench Version: 5.10 //****************************************************************************** #include void main (void) { WDTCTL = WDTPW + WDTHOLD; P1DIR |= 0x01; CACTL1 = CARSEL + CAREF0 + CAON; CACTL2 = P2CA4; } while (1) { if ((CAOUT & CACTL2)) P1OUT |= 0x01; else P1OUT &= ~0x01; } // // // // Stop WDT P1.0 output 0.25 Vcc = -comp, on P1.1/CA1 = +comp // Test comparator_A output // if CAOUT set, set P1.0 // else reset