/* --COPYRIGHT--,BSD_EX * Copyright (c) 2012, Texas Instruments Incorporated * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * * Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * * Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * * Neither the name of Texas Instruments Incorporated nor the names of * its contributors may be used to endorse or promote products derived * from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. * ******************************************************************************* * * MSP430 CODE EXAMPLE DISCLAIMER * * MSP430 code examples are self-contained low-level programs that typically * demonstrate a single peripheral function or device feature in a highly * concise manner. For this the code may rely on the device's power-on default * register values and settings such as the clock configuration and care must * be taken when combining code from several examples to avoid potential side * effects. Also see www.ti.com/grace for a GUI- and www.ti.com/msp430ware * for an API functional library-approach to peripheral configuration. * * --/COPYRIGHT--*/ //****************************************************************************** // MSP430F20xx Demo - Timer_A, Toggle P1.1/TA0, Up/Down Mode, 32kHz ACLK // // Description: Toggle P1.1 using hardware TA0 output. Timer_A is configured // for up/down mode with CCR0 defining period, TA0 also output on P1.1. In // this example, CCR0 is loaded with 5 and TA0 will toggle P1.1 at TACLK/2*5. // Thus the output frequency on P1.1 will be the TACLK/20. No CPU or software // resources required. Normal operating mode is LPM3. // ACLK = TACLK = 32kHz, MCLK = default DCO // As coded with TACLK = ACLK, P1.1 output frequency = 32768/20 = 1.6384kHz // //* External watch crystal installed on XIN XOUT is required for ACLK *// // // MSP430F20xx // ----------------- // /|\| XIN|- // | | | 32 kHz // --|RST XOUT|- // | | // | P1.1/TA0|--> ACLK/20 // // M. Buccini / L. Westlund // Texas Instruments Inc. // October 2005 // Built with CCE Version: 3.2.0 and IAR Embedded Workbench Version: 3.40A //****************************************************************************** #include int main(void) { WDTCTL = WDTPW + WDTHOLD; // Stop WDT P1DIR |= 0x02; // P1.1 output P1SEL |= 0x02; // P1.1 option select CCTL0 = OUTMOD_4; // CCR0 toggle mode CCR0 = 5; TACTL = TASSEL_1 + MC_3; // ACLK, up-downmode __bis_SR_register(LPM3_bits); // Enter LPM3 }