//****************************************************************************** // MSP430G2xx2 Demo - USI SPI Interface to TLC549 8-bit ADC // // Description: This program demonstrates the USI in SPI mode interface to a // TLC549 8-bit ADC If AIN > 0.5(REF+ - REF-), P1.0 set, else reset // ACLK = n/a, MCLK = SMCLK = default DCO, UCICLK = SMCLK/4 // //** VCC must be at least 3v for TLC549 **// // // MSP430G2xx2 // // /|\| XIN|// TLC549 | | | // |RST XOUT|// | CS|< -|P1.1 | // | DATAOUT| ->|P1.7/SOMI P1.0| >LED // ~>|AIN I/O CLK|< -|P1.5/SCLK | // // 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; // Stop watchdog timer P1OUT = 0; P1DIR |= 0x03; USICTL0 |= USIPE7 + USIPE5 + USIMST + USIOE; // Port, SPI master USICTL1 |= USIIE; // Counter interrupt, flag remains set USICKCTL = USIDIV_2 + USISSEL_2; // /4 SMCLK USICTL0 &= ~USISWRST; // USI released for operation USICNT = 8; // init-load counter _BIS_SR(LPM0_bits + GIE); // Enter LPM0 w/ interrupt } // USI interrupt service routine #pragma vector=USI_VECTOR interrupt void universal_serial_interface(void) { P1OUT |= 0x02; // Disable TLC549 if (USISRL > 0x7F) P1OUT |= 0x01; else P1OUT &= ~0x01; P1OUT &= ~0x02; // Enable TLC549 USICNT = 8; // re-load counter }