;******************************************************************************* ; MSP430F20x2/3 Demo - USI SPI Interface to TLC549 8-bit ADC ; ; Description: This program demonstrate a 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 **// ; ; MSP430F20x2/3 ; ; /|\| XIN|; TLC549 | | | ; |RST XOUT|; | CS|< -|P1.1 | ; | DATAOUT| ->|P1.7/SOMI P1.0| >LED ; ~>|AIN I/O CLK|< -|P1.5/UCLK0 | ; ; M.Buccini / L Westlund ; Texas Instruments, Inc ; October 2005 ; Built with IAR Embedded Workbench Version: 3.40A ;******************************************************************************* #include "msp430x20x3.h" ; ORG 0F800h ; Program Reset ; RESET mov.w #0280h,SP ; Initialize stackpointer StopWDT mov.w #WDTPW+WDTHOLD,&WDTCTL ; Stop watchdog timer SetupP1 clr.b &P1OUT ; bis.b #03h,&P1DIR ; P1.0/1 output direction SetupUSI bis.b bis.b mov.b bic.b mov.b #USIPE7+USIPE5+USIMST+USIOE,&USICTL0; Port, SPI master #USIIE,&USICTL1 ; Counter interrupt, flag remains #USIDIV_2+USISSEL_2,&USICKCTL ; /4 SMCLK #USISWRST,&USICTL0 ; Enable USI #08h,&USICNT ; init-load counter, clears flag ; Mainloop bis.w #LPM0+GIE,SR ; Enter LPM0, enable interrupts jmp Mainloop ; Again ; ; USI_ISR ; ; bis.b #02h,&P1OUT ; Disable TLC549 cmp.b #07Fh,&USISRL ; bic.b #01h,&P1OUT ; jlo USI_ISR1 ; bis.b #01h,&P1OUT ; USI_ISR1 bic.b #02h,&P1OUT ; Enable TLC549 mov.b #08h,&USICNT ; re-load counter reti ; ; ; ; Interrupt Vectors Used MSP430x2013 ; ORG 0FFFEh ; MSP430 RESET Vector DW RESET ; ORG 0FFE8h ; USICNT DW USI_ISR ; END