#include "msp430.h" ; #define controlled include file SCL EQU 2 ; I2C bus setup SDA EQU 1 pressTsch EQU 03Fh + 1 ; threscholds for button press and releaseTsch EQU 0FCh ; release (for the shift register) RSEG CSTACK ; stack segment RSEG DATA16_N ; data segment btState DS 1 ; buttons state shiftH DS 1 ; shift reg for debouncing shiftM DS 1 ; same for the set minutes button seconds DS 1 ; counter for seconds hrsT DS 1 ; storage for hours (tens) hrsU DS 1 ; - " - (units) minT DS 1 ; storage for minutes (tens) minU DS 1 ; - " - (units) RSEG CODE ; code segment main mov #SFE(CSTACK), SP ; set up stack mov.w #WDTPW+WDTHOLD, &WDTCTL ; stop watch dog timer bic.b #XCAP_3, &BCSCTL3 ; set up 6 pF crystal load caps bic.w #OSCOFF, SR ; enable crystal oscillator mov.b #0FFh, &P1DIR ; enable P1<7:0> for output mov.b #01Ah, &P2DIR ; enable input on P2.5, P2.2, P2.0 mov.b #BIT5+BIT2, &P2REN ; enable pull up/down resistors bis.b #BIT5+BIT2, &P2OUT ; select pull-up resistors clr.b &P1OUT bic.b #BIT3+BIT4, &P2OUT bis.b #BIT3+BIT4, &P2OUT ; turn off all digits bic.b #BIT3+BIT4, &P2OUT clr.b R8 ; colon state mov.b #1, R14 ; active digit code (1,2,4,8) mov.b R14, R13 ; active digit index (1 - 4) mov.w #16, R5 mov.w R5, &TACCR1 ; initial brightness setup mov.w #CCIE, &TACCTL1 ; enable CCR1 interrupt mov.w #127, &TACCR0 ; set up Timer_A upper counting limit mov.w #TASSEL_1+MC_1+TAIE, &TACTL ; ACLK, up mode, interrupt mov.b #0FFh, &shiftH ; initialize shift regs mov.b #0FFh, &shiftM ; for buttons debouncing mov.b #3, &btState ; initial buttons state "all up" init_RTC bit.b #SDA, &P2IN ; initialize the I2C interface jnz I2C_OK ; by toggling clock line bis.b #SCL, &P2OUT ; until the data line gets high jmp $+2 bic.b #SCL, &P2OUT jmp init_RTC I2C_OK call #start_I2C ; configure RTC mov.b #11010000b, R10 ; slave address/write call #write_I2C mov.b #0Eh, R10 ; config reg pointer call #write_I2C mov.b #4, R10 ; disable alarms and frequency call #write_I2C ; output call #stop_I2C loop clr.w R15 ; clear time counter of 1-sec intervals call #start_I2C ; get time from RTC mov.b #11010000b, R10 ; slave address/write call #write_I2C clr.b R10 ; seconds register address call #write_I2C call #start_I2C mov.b #11010001b, R10 ; slave address/read call #write_I2C clr.b R12 ; ACK signal call #read_I2C ; get seconds in R10 mov.b R10, R15 ; convert seconds from BCD and.b #0xF0, R15 ; into binary representation in R15 rla R15 rla R15 ; since R15 counts the # of 1/256sec add.w R10, R15 ; intervals, it must be multiplied rra R15 ; by 256 afterwards to be consistent rra R15 ; with the rest of the code rra R15 bic #BIT0, R15 and.b #0x0F, R10 add R10, R15 ; conversion is completed here dec.b R15 ; make sure that RTC and CPU are in sync jge $+6 ; by decrementing R15 (mod 60) mov.b #59, R15 swpb R15 ; R15 *= 256 call #read_I2C ; get minutes and save them mov.b R10, &minU and.b #0Fh, &minU rra.b R10 rra.b R10 rra.b R10 rra.b R10 and.b #7, R10 mov.b R10, &minT inc.b R12 ; NAK signal call #read_I2C ; get hours and save them call #stop_I2C mov.b R10, &hrsU and.b #0Fh, &hrsU rra.b R10 rra.b R10 rra.b R10 rra.b R10 and.b #3, R10 jne $+6 mov.b #12, R10 ; do not display a leading 0 mov.b R10, &hrsT get_ADC call #start_I2C ; adjust LED brightness mov.b #10100011b, R10 ; request ADC conversion call #write_I2C clr.b R12 ; ACK signal call #read_I2C mov.b R10, R5 ; get high-order byte swpb R5 inc.b R12 ; NACK signal call #read_I2C call #stop_I2C add.w R10, R5 ; add lower-order byte rra.w R5 ; format ADC core in R5 to load into rra.w R5 ; PWM brightness control register rra.w R5 ; TACCR1 = ADC/32 + 4 rra.w R5 rra.w R5 add #4, R5 cmp.w #128, R5 ; make sure that PWM duty cycle code jlo $+6 ; does not exceed 127 which corresponds mov.b #127, R5 ; to 100% brightness mov.w R5, &TACCR1 ; load brightness control register wait_l bis.w #LPM2+GIE, SR ; enter LPM2, interrupts enabled bit.b #BIT0, R15 ; debounce the buttons every other jne checkSecond ; interrupt, i.e. once in 8 msec debounceH clrc rrc.b &shiftH ; debouncing the hours setup button bit.b #BIT5, &P2IN ; shift in the button value jz $+8 bis.b #BIT7, &shiftH bit.b #BIT1, &btState ; old state == "up" ? jz debounce1 ; NO - it is "down" cmp.b #pressTsch, &shiftH jhs debounceM bic.b #BIT1, &btState ; set new state = "down" inc.b &hrsU ; update units of hours mov.b #10, R10 cmp.b #2, &hrsT jne $+4 mov.b #4, R10 cmp.b R10, &hrsU jne uh_end clr.b &hrsU ; update tens inc.b &hrsT cmp.b #3, &hrsT jlo uh_end jeq exit2 mov.b #1, &hrsT jmp uh_end exit2 mov.b #12, &hrsT ; empty digit uh_end call #setTime ; load updated time into RTC jmp debounceM debounce1 cmp.b #releaseTsch, &shiftH jlo debounceM bis.b #BIT1, &btState ; set new state = "up" debounceM clrc rrc.b &shiftM ; debouncing the minutes setup button bit.b #BIT2, &P2IN jz $+8 bis.b #BIT7, &shiftM bit.b #BIT0, &btState ; old state == "up" ? jz debounce2 ; NO - it is "down" cmp.b #pressTsch, &shiftM jhs checkSecond bic.b #BIT0, &btState ; set new state = "down" inc.b &minU ; update units of minutes cmp.b #10, &minU jne um_end clr.b &minU ; clear units inc.b &minT ; update tens cmp.b #6, &minT jne um_end clr.b &minT ; clear tens um_end call #setTime ; load updated time into RTC jmp checkSecond debounce2 cmp.b #releaseTsch, &shiftM jlo checkSecond bis.b #BIT0, &btState ; set new state = "up" checkSecond inc.w R15 ; counter of interrupt intervals bit.b #0FFh, R15 ; is it a 1-sec time stamp? jne wait_l ; NO - wait xor.b #BIT7, R8 ; YES - flip colon every second cmp.w #15360, R15 ; is it a 1 minute time stamp? (15360) jeq loop ; YES -get time and brightness cmp.w #3840, R15 ; NO - check for a 15-sec interval jeq get_ADC ; adjust brightness cmp.w #7680, R15 ; check for a 30-sec interval jeq get_ADC cmp.w #11520, R15 ; check for a 45-sec interval jeq get_ADC jmp wait_l ; no adjustment is needed - wait ;///////////////////// ISRs //////////////////////////////////////////////// TA_ISR add.w &TAIV, PC ; Add Timer_A offset vector reti ; CCR0 - no source jmp CCR1_ISR ; CCR1 reti ; CCR2 reti ; reserved reti ; reserved rla.b R14 ; update active digit code inc.b R13 ; update digit index bit.b #BIT4, R14 jz $+6 ; the upper limit is not reached yet mov.b #1, R14 ; reset the active digit # to 1 mov.b R14, R13 mov.b R14, &P1OUT ; set new active digit bis.b #BIT3, &P2OUT ; latch it in bic.b #BIT3, &P2OUT mov.b seconds(R13), R10 ; get digit mov.b code7(R10), &P1OUT ; move new data to output reg bit.b #BIT1, R13 ; colon processing for digit codes jz $+6 ; 2 and 3 add.b R8, &P1OUT bis.b #BIT4, &P2OUT ; latch it in bic.b #BIT4, &P2OUT bic.w #LPM2, 0(SP) ; return from sleep reti ;--------------------------------------------------------------------------- CCR1_ISR clr.b &P1OUT ; turn off all digits bis.b #BIT4, &P2OUT bic.b #BIT4, &P2OUT bic.w #CCIFG, &TACCTL1 ; clear interrupt flag reti ;///////////////////// PROCEDURES ///////////////////////////////////////// ; ___ ; DATA: |_______ ; ______ ; SCK : |___ ; start_I2C ; I2C start condition bic.b #SDA, &P2OUT bic.b #SDA, &P2DIR ; start with SDA=1 and SCL=1 bis.b #SCL, &P2OUT bis.b #SDA, &P2DIR ; set dala low jmp $+2 jmp $+2 nop bic.b #SCL, &P2OUT ; set clock low ret ;--------------------------------------------------------------------------- ; ___ ; DATA: ______| ; ______ ; SCK : ___| ; stop_I2C ; I2C stop condition bis.b #SCL, &P2OUT ; set clock high jmp $+2 jmp $+2 nop bic.b #SDA, &P2DIR ; set data high ret ;--------------------------------------------------------------------------- write_I2C ; send a byte in R10 into I2C bic.b #SDA, &P2DIR ; make sure that DATA=1 and CLK=0 bic.b #SCL, &P2OUT mov.b #8, R11 ; initialize bit counter w_loop rlc.b R10 ; get the leftmost data bit jc $+8 bis.b #SDA, &P2DIR ; set 0 on data line jmp $+6 bic.b #SDA, &P2DIR ; set 1 on data line bis.b #SCL, &P2OUT ; raise clock up jmp $+2 ; short delay jmp $+2 nop bic.b #SCL, &P2OUT ; ... and low dec.b R11 jnz w_loop ; repeat this 8 times bic.b #SDA, &P2DIR ; release the data line jmp $+2 ; let slave respond for ACK bis.b #SCL, &P2OUT ; clock up jmp $+2 ; slave responds OK (hopefully) jmp $+2 nop bic.b #SCL, &P2OUT ; clock down ret ;--------------------------------------------------------------------------- read_I2C ; read byte from I2C into R10 bic.b #SDA, &P2DIR ; make sure that DATA=1 and CLK=0 bic.b #SCL, &P2OUT mov.b #8, R11 ; initialize bit counter r_loop bis.b #SCL, &P2OUT ; clock up bit.b #SDA, &P2IN ; received bit -> C-bit rlc.b R10 ; shift it into R10 jmp $+2 nop bic.b #SCL, &P2OUT ; clock down jmp $+2 dec.b R11 jnz r_loop ; repeat this 8 times tst.b R12 ; R12 = ACK jnz $+6 bis.b #SDA, &P2DIR ; send ACK signal jmp $+2 bis.b #SCL, &P2OUT ; raise clock up jmp $+2 ; short delay jmp $+2 nop bic.b #SCL, &P2OUT ; ... and low bic.b #SDA, &P2DIR ; release the data line ret ;--------------------------------------------------------------------------- setTime ; set time in DS1337 call #start_I2C mov.b #11010000b, R10 ; slave address/write call #write_I2C mov.b #1, R10 ; minutes register address call #write_I2C mov.b &minT, R10 and.b #7, R10 rla.b R10 rla.b R10 rla.b R10 rla.b R10 add.b &minU, R10 call #write_I2C ; set minutes mov.b &hrsT, R10 and.b #3, R10 rla.b R10 rla.b R10 rla.b R10 rla.b R10 add.b &hrsU, R10 ; set hours call #write_I2C call #stop_I2C ret ;--------------------------------------------------------------------------- code7 ; pabcdefg ; 7-segment codes DB 01111110b ; code for 0 DB 00110000b ; code for 1 DB 01101101b ; code for 2 DB 01111001b ; code for 3 DB 00110011b ; code for 4 DB 01011011b ; code for 5 DB 01011111b ; code for 6 DB 01110000b ; code for 7 DB 01111111b ; code for 8 DB 01111011b ; code for 9 DB 00000001b ; code for - DB 01000111b ; code for F DB 00000000b ; empty ;--------------------------------------------------------------------------- COMMON INTVEC ; MSP430F2101 interrupt vectors ORG RESET_VECTOR DC16 main ; set reset vector to 'main' label ORG TIMERA1_VECTOR DC16 TA_ISR ; set timer_A interrupt vector END