static volatile unsigned int irq_events = 0;
enum {ev_btn1 = 0, ev_btn2, ev_pir1, ev_pir2, ev_tmr, ev_adc, ev_MAX};
+#define PWM_ORDER 10
+#define PWM_HALF 5
+#define LIGHT_THRESHOLD 900
+#define TIME_ON 320
+
#ifdef ADCSC /* Let us hope that this is a "new" model */
# define BIT_RL BIT0
# define BIT_GL BIT1
# define BIT_BTN2 0
#endif
+static int expon2(int duty)
+{
+ int shift = duty>>1;
+ int comp = 1<<shift;
+ int extra = (duty & 1) ? comp>>1 : 0;
+ return (duty ? comp|extra : 0);
+}
+
int main(void)
{
- int Duty_Cycle = 1;
+ int Duty_Cycle = 0;
int Increment = 1;
- unsigned int Time_Count = 0;
- unsigned int Time_Left = 5;
+ unsigned int Time_Left = 50;
+ unsigned int Time_Indicate = 2;
WDTCTL = WDTPW | WDTHOLD; // stop watchdog timer
// Configure GPIO Out
- P1DIR |= BIT_RL|BIT_GL|BIT7; // Set LEDs & PWM to output direction
+ P1DIR |= BIT_RL|BIT_GL|BIT2; // Set LEDs & PWM to output direction
P1OUT &= ~(BIT_RL|BIT_GL); // LEDs off
#ifdef P1SEL1
- P1SEL1 |= BIT7; // PWM out
+ P1SEL1 |= BIT2; // PWM out
#else
- P1SEL |= BIT7; // PWM out
+ P1SEL |= BIT2; // PWM out
#endif
// Configure GPIO In
// channel 5 is unused, reserved for measuring current
#endif
- // Timer and ADC
+ // Timer and PWM
#ifndef TASSEL__SMCLK
# define TASSEL__SMCLK TASSEL_2
-#endif
-#ifndef MC__UP
# define MC__UP MC_1
-#endif
-#ifndef MC__CONTINUOUS
# define MC__CONTINUOUS MC_2
+# define TA0CCR2 TA0CCR1
+# define TA0CCTL2 TA0CCTL1
#endif
// Configure timer A0 for PWM
- TA0CCR0 = 10000-1; // PWM Period
- TA0CCTL2 = OUTMOD_7; // CCR2 reset/set
- TA0CCR2 = 500; // CCR2 PWM duty cycle
- TA0CTL = TASSEL__SMCLK | MC__UP | TACLR;// SMCLK, up mode, clear TAR
+ TA0CCR0 = 1 << PWM_ORDER; // PWM Period 2^10 ca. 1 kHz
+ TA0CCR2 = 0; // CCR1 PWM duty cycle
+ TA0CCTL2 = OUTMOD_7; // CCR1 reset/set
+ TA0CTL = TASSEL__SMCLK | MC__UP | TACLR;// SMCLK, up mode
+ // SMCLK, no divider, up mode, no interrupt, clear TAR
//Configure timer A1 for counting time
TA1CTL |= TASSEL__SMCLK | MC__CONTINUOUS | TACLR | TAIE;
irq_events = 0;
_enable_interrupts();
- // Button 2 or PIR events initiate light measurement and tuns on green led
+ // Button 2 or PIR events initiate light measurement
+ // and tuns on green or red led
if (events & (1<<ev_btn2|1<<ev_pir1|1<<ev_pir2)) {
- if (Duty_Cycle > 1) {
- Time_Left = 15;
- continue;
- }
+ if (events & 1<<ev_pir1)
+ P1OUT |= BIT_GL; // Set green LED on
+ if (events & 1<<ev_pir2)
+ P1OUT |= BIT_RL; // Set red LED on
// Sampling and conversion start
#ifdef ADCENC
ADCCTL0 |= ADCENC | ADCSC;
#else
ADC10CTL0 |= ENC + ADC10SC;
#endif
- P1OUT |= BIT_GL; // Set green LED on
}
- // End of light measurement,
- // set new Duty_Cycle and zero increment and turn off green led
+ // End of light measurement. Set new Duty_Cycle,
+ // zero increment and turn off green led
if (events & 1<<ev_adc) {
- P1OUT &= ~BIT_GL; // Clear green LED off
- if (Time_Left)
- continue;
- if (ADC_Result < 200)
+ P1OUT ^= (BIT_GL|BIT_RL); // Flip green and red LEDs
+ Time_Indicate = 5;
+ if (ADC_Result < LIGHT_THRESHOLD)
continue;
- Time_Left = 15;
+ Time_Left = TIME_ON;
Increment = 1;
}
// Button 1 sets non-zero increment (and toggles it)
if (events & 1<<ev_btn1) {
- if (Duty_Cycle > 5000) {
+ P1OUT |= (BIT_GL|BIT_RL); // Set green and red LEDs on
+ Time_Indicate = 5;
+ if (Duty_Cycle > PWM_HALF) {
Time_Left = 0;
Increment = -1;
} else {
- Time_Left = 15;
+ Time_Left = TIME_ON;
Increment = 1;
}
}
// Timer event (100 ms) changed duty cycle and flashes red led
if (events & 1<<ev_tmr) {
- if (Time_Count++ > 10) {
- Time_Count = 0;
- P1OUT ^= BIT_RL; // blink
- if (Time_Left)
- Time_Left--;
- else if (Duty_Cycle > 1)
- Increment = -1;
- }
- if (Increment == 0)
- continue;
- else if (Increment > 0)
- Duty_Cycle *= 2;
- else if (Increment < 0)
- Duty_Cycle /= 2;
- if (Duty_Cycle < 1) {
- Duty_Cycle = 1;
- Increment = 0;
+ if (Time_Indicate) {
+ Time_Indicate--;
+ if (!Time_Indicate)
+ P1OUT &= ~(BIT_RL|BIT_GL); // LEDs off
}
- if (Duty_Cycle > (10000-1)) {
- Duty_Cycle = 10000-1;
- Increment = 0;
+ if (Time_Left) {
+ Time_Left--;
+ if (!Time_Left)
+ if (Duty_Cycle)
+ Increment = -1;
}
- TA0CCR2 = Duty_Cycle;
+ if (Increment > 0) {
+ if (++Duty_Cycle >= (PWM_ORDER<<1)) {
+ Duty_Cycle = PWM_ORDER<<1;
+ Increment = 0;
+ }
+ } else if (Increment < 0) {
+ if (--Duty_Cycle < 1) {
+ Duty_Cycle = 0;
+ Increment = 0;
+ }
+ } else // Increment _was_ zero - no change!
+ continue;
+
+ TA0CCR2 = expon2(Duty_Cycle);
}
__bis_SR_register(LPM0_bits | GIE);
__no_operation();
#error Compiler not supported!
#endif
{
+ if (P2IFG & BIT4) {
+ irq_events |= 1<<ev_pir1;
+ P2IFG &= ~BIT4; // Clear P2.4 IFG
+ }
+ if (P2IFG & BIT5) {
+ irq_events |= 1<<ev_pir2;
+ P2IFG &= ~BIT5; // Clear P2.5 IFG
+ }
+#if (PBTN() == P1)
+ __bic_SR_register_on_exit(LPM0_bits); // Wake up
+}
+// GPIO interrupt service routine
+#if defined(__TI_COMPILER_VERSION__) || defined(__IAR_SYSTEMS_ICC__)
+#pragma vector=PORT1_VECTOR
+__interrupt void Port_1(void)
+#elif defined(__GNUC__)
+void __attribute__ ((interrupt(PORT1_VECTOR))) Port_1 (void)
+#else
+#error Compiler not supported!
+#endif
+{
+#endif /* (PBTN() == P1) */
if (PBTN(IFG) & BIT_BTN) {
irq_events |= 1<<ev_btn1;
PBTN(IFG) &= ~BIT_BTN; // Clear button IFG
PBTN(IFG) &= ~BIT_BTN2; // Clear button 2 IFG
}
#endif
- if (P2IFG & BIT4) {
- irq_events |= 1<<ev_pir1;
- P2IFG &= ~BIT4; // Clear P2.4 IFG
- }
- if (P2IFG & BIT5) {
- irq_events |= 1<<ev_pir2;
- P2IFG &= ~BIT5; // Clear P2.5 IFG
- }
__bic_SR_register_on_exit(LPM0_bits); // Wake up
}