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+/*
+ ************************************************************************
+ * wiring_analog.c
+ *
+ * Arduino core files for MSP430
+ * Copyright (c) 2012 Robert Wessels. All right reserved.
+ *
+ *
+ ***********************************************************************
+ Derived from:
+ wiring_analog.c - analog input and output
+ Part of Arduino - http://www.arduino.cc/
+
+ Copyright (c) 2005-2006 David A. Mellis
+
+ This library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ This library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General
+ Public License along with this library; if not, write to the
+ Free Software Foundation, Inc., 59 Temple Place, Suite 330,
+ Boston, MA 02111-1307 USA
+*/
+
+#include "wiring_private.h"
+#include "pins_energia.h"
+
+#if defined(__MSP430_HAS_ADC10__) && !defined(ADC10ENC)
+#define ADC10ENC ENC
+#endif
+#if defined(__MSP430_HAS_ADC10__) && !defined(ADC10MEM0)
+#define ADC10MEM0 ADC10MEM
+#endif
+#if defined(__MSP430_HAS_ADC10_B__)
+#define REFV_MASK 0x70
+#define REF_MASK 0x31;
+#endif
+
+#if defined(__MSP430_HAS_ADC10__) || defined(__MSP430_HAS_ADC10_B__)
+uint16_t analog_reference = DEFAULT, analog_period = F_CPU/490, analog_div = 0, analog_res=255; // devide clock with 0, 2, 4, 8
+#endif
+
+void analogReference(uint16_t mode)
+{
+ // can't actually set the register here because the default setting
+ // will connect AVCC and the AREF pin, which would cause a short if
+ // there's something connected to AREF.
+ analog_reference = mode;
+}
+
+//TODO: Can be a lot more efficiant.
+// - lower clock rated / input devider to conserve Energia.
+// - pin configuration logic.
+
+// Note set frequency before sending analog value
+// Lowest fequency is defined by clock frequency F_CPU, and max counter value 2^16-1
+// fmin = F_CPU / 2^16
+void analogFrequency(uint32_t freq)
+{
+ if ( freq <= F_CPU/(4*65334L) ) { analog_div = ID_3; freq *=8; }
+ else if ( freq <= F_CPU/(2*65334L) ) { analog_div = ID_2; freq *=4; }
+ else if ( freq <= F_CPU/(4*65334L) ) { analog_div = ID_1; freq *=2; }
+ analog_period = F_CPU/freq;
+}
+
+// Set the resulution (nr of counts for 100%), default = 255, large values may not work at all frequencies
+void analogResolution(uint16_t res)
+{
+ analog_res = res;
+}
+
+//Arduino specifies ~490 Hz for analog out PWM so we follow suit.
+#define PWM_PERIOD analog_period // F_CPU/490
+#define PWM_DUTY(x) ( (unsigned long)x*PWM_PERIOD / (unsigned long)analog_res )
+void analogWrite(uint8_t pin, int val)
+{
+ pinMode(pin, OUTPUT); // pin as output
+
+ if (val == 0)
+ {
+ digitalWrite(pin, LOW); // set pin to LOW when duty cycle is 0
+ // digitalWrite will take care of invalid pins
+ }
+ else if (val == analog_res)
+ {
+ digitalWrite(pin, HIGH); // set pin HIGH when duty cycle is 255
+ // digitalWrite will take care of invalid pins
+ }
+ else
+ {
+
+ uint8_t bit = digitalPinToBitMask(pin); // get pin bit
+ uint8_t port = digitalPinToPort(pin); // get pin port
+ volatile uint8_t *sel;
+
+ if (port == NOT_A_PORT) return; // pin on timer?
+
+ sel = portSelRegister(port); // get the port function select register address
+ *sel |= bit; // set bit in pin function select register
+
+ switch(digitalPinToTimer(pin)) { // which timer and CCR?
+ //case: T0A0 // CCR0 used as period register
+ case T0A1: // TimerA0 / CCR1
+ TA0CCR0 = PWM_PERIOD; // PWM Period
+ TA0CCTL1 = OUTMOD_7; // reset/set
+ TA0CCR1 = PWM_DUTY(val); // PWM duty cycle
+ TA0CTL = TASSEL_2 + MC_1 + analog_div; // SMCLK, up mode
+ break;
+#if defined(__MSP430_HAS_TA3__) || defined(__MSP430_HAS_T0A3__)
+ case T0A2: // TimerA0 / CCR2
+ TA0CCR0 = PWM_PERIOD; // PWM Period
+ TA0CCTL2 = OUTMOD_7; // reset/set
+ TA0CCR2 = PWM_DUTY(val); // PWM duty cycle
+ TA0CTL = TASSEL_2 + MC_1+ analog_div; // SMCLK, up mode
+ break;
+#endif
+#if defined(__MSP430_HAS_T1A3__)
+ //case: T1A0 // CCR0 used as period register
+ case T1A1: // TimerA1 / CCR1
+ TA1CCR0 = PWM_PERIOD; // PWM Period
+ TA1CCTL1 = OUTMOD_7; // reset/set
+ TA1CCR1 = PWM_DUTY(val); // PWM duty cycle
+ TA1CTL = TASSEL_2 + MC_1+ analog_div; // SMCLK, up mode
+ break;
+ case T1A2: // TimerA1 / CCR2
+ TA1CCR0 = PWM_PERIOD; // PWM Period
+ TA1CCTL2 = OUTMOD_7; // reset/set
+ TA1CCR2 = PWM_DUTY(val); // PWM duty cycle
+ TA1CTL = TASSEL_2 + MC_1+ analog_div; // SMCLK, up mode
+ break;
+#endif
+#if defined(__MSP430_HAS_T2A3__)
+ //case: T2A0 // CCR0 used as period register
+ case T2A1: // TimerA2 / CCR1
+ TA2CCR0 = PWM_PERIOD; // PWM Period
+ TA2CCTL1 = OUTMOD_7; // reset/set
+ TA2CCR1 = PWM_DUTY(val); // PWM duty cycle
+ TA2CTL = TASSEL_2 + MC_1+ analog_div; // SMCLK, up mode
+ break;
+ case T2A2: // TimerA2 / CCR2
+ TA2CCR0 = PWM_PERIOD; // PWM Period
+ TA2CCTL2 = OUTMOD_7; // reset/set
+ TA2CCR2 = PWM_DUTY(val); // PWM duty cycle
+ TA2CTL = TASSEL_2 + MC_1+ analog_div; // SMCLK, up mode
+ break;
+#endif
+#if defined(__MSP430_HAS_T0B3__)
+ //case: T0B0 // CCR0 used as period register
+ case T0B1: // TimerB0 / CCR1
+ TB0CCR0 = PWM_PERIOD; // PWM Period
+ TB0CCTL1 = OUTMOD_7; // reset/set
+ TB0CCR1 = PWM_DUTY(val); // PWM duty cycle
+ TB0CTL = TBSSEL_2 + MC_1+ analog_div; // SMCLK, up mode
+ break;
+ case T0B2: // TimerB0 / CCR1
+ TB0CCR0 = PWM_PERIOD; // PWM Period
+ TB0CCTL2 = OUTMOD_7; // reset/set
+ TB0CCR2 = PWM_DUTY(val); // PWM duty cycle
+ TB0CTL = TBSSEL_2 + MC_1+ analog_div; // SMCLK, up mode
+ break;
+#endif
+#if defined(__MSP430_HAS_T1B3__)
+ //case: T1B0 // CCR0 used as period register
+ case T1B1: // TimerB0 / CCR1
+ TB1CCR0 = PWM_PERIOD; // PWM Period
+ TB1CCTL1 = OUTMOD_7; // reset/set
+ TB1CCR1 = PWM_DUTY(val); // PWM duty cycle
+ TB1CTL = TBSSEL_2 + MC_1+ analog_div; // SMCLK, up mode
+ break;
+ case T1B2: // TimerB0 / CCR1
+ TB1CCR0 = PWM_PERIOD; // PWM Period
+ TB1CCTL2 = OUTMOD_7; // reset/set
+ TB1CCR2 = PWM_DUTY(val); // PWM duty cycle
+ TB1CTL = TBSSEL_2 + MC_1+ analog_div; // SMCLK, up mode
+ break;
+#endif
+#if defined(__MSP430_HAS_T2B3__)
+ //case: T1B0 // CCR0 used as period register
+ case T2B1: // TimerB0 / CCR1
+ TB2CCR0 = PWM_PERIOD; // PWM Period
+ TB2CCTL1 = OUTMOD_7; // reset/set
+ TB2CCR1 = PWM_DUTY(val); // PWM duty cycle
+ TB2CTL = TBSSEL_2 + MC_1+ analog_div; // SMCLK, up mode
+ break;
+ case T2B2: // TimerB0 / CCR1
+ TB2CCR0 = PWM_PERIOD; // PWM Period
+ TB2CCTL2 = OUTMOD_7; // reset/set
+ TB2CCR2 = PWM_DUTY(val); // PWM duty cycle
+ TB2CTL = TBSSEL_2 + MC_1+ analog_div; // SMCLK, up mode
+ break;
+#endif
+
+ case NOT_ON_TIMER: // not on a timer output pin
+ default: // or TxA0 pin
+ if (val <= (analog_res >> 1)) {
+ digitalWrite(pin, LOW); //
+ } else {
+ digitalWrite(pin, HIGH);
+ }
+ }
+ }
+}
+
+uint16_t analogRead(uint8_t pin)
+{
+// make sure we have an ADC
+#if defined(__MSP430_HAS_ADC10__) || defined(__MSP430_HAS_ADC10_B__)
+ // 0000 A0
+ // 0001 A1
+ // 0010 A2
+ // 0011 A3
+ // 0100 A4
+ // 0101 A5
+ // 0110 A6
+ // 0111 A7
+ // 1010 Internal temperature sensor
+
+ //TODO: Only int. temp. sensor requires Tsample > 30us.
+ // The below ADC configuration applies this rule to all channels right now.
+ // ADC10CLK = 5MHz / 5 = 1Mhz
+ // Tsample = S&H / ADC10CLK = 64 / 1 MHz = 64 us
+ // Tconvert = 13 / ADC10CLK = 13 / 1 MHz = 13 us
+ // Total time per sample = Tconvert + Tsample = 64 + 13 = 67 us = ~15k samples / sec
+
+ ADC10CTL0 &= ~ADC10ENC; // disable ADC
+ ADC10CTL1 = ADC10SSEL_0 | ADC10DIV_5; // ADC10OSC as ADC10CLK (~5MHz) / 5
+#if defined(__MSP430_HAS_ADC10__)
+ ADC10CTL0 = analog_reference | // set analog reference
+ ADC10ON | ADC10SHT_3 | ADC10IE; // turn ADC ON; sample + hold @ 64 × ADC10CLKs; Enable interrupts
+ ADC10CTL1 |= (pin << 12); // select channel
+ ADC10AE0 = (1 << pin); // Disable input/output buffer on pin
+#endif
+#if defined(__MSP430_HAS_ADC10_B__)
+ while(REFCTL0 & REFGENBUSY); // If ref generator busy, WAIT
+ REFCTL0 |= analog_reference & REF_MASK; // Set reference using masking off the SREF bits. See Energia.h.
+ ADC10MCTL0 = pin | (analog_reference & REFV_MASK); // set channel and reference
+ ADC10CTL0 = ADC10ON | ADC10SHT_4; // turn ADC ON; sample + hold @ 64 × ADC10CLKs
+ ADC10CTL1 |= ADC10SHP; // ADCCLK = MODOSC; sampling timer
+ ADC10CTL2 |= ADC10RES; // 10-bit resolution
+ ADC10IFG = 0; // Clear Flags
+ ADC10IE |= ADC10IE0; // Enable interrupts
+#endif
+ __delay_cycles(128); // Delay to allow Ref to settle
+ ADC10CTL0 |= ADC10ENC | ADC10SC; // enable ADC and start conversion
+ while (ADC10CTL1 & ADC10BUSY) { // sleep and wait for completion
+ __bis_SR_register(CPUOFF + GIE); // LPM0 with interrupts enabled
+ }
+
+#if defined(__MSP430_HAS_ADC10__)
+ /* POWER: Turn ADC and reference voltage off to conserve power */
+ ADC10CTL0 &= ~(ADC10ON | REFON);
+#endif
+
+#if defined(__MSP430_HAS_ADC10_B__)
+ /* POWER: Turn ADC and reference voltage off to conserve power */
+ ADC10CTL0 &= ~(ADC10ON);
+ REFCTL0 &= ~REFON;
+#endif
+ return ADC10MEM0; // return sampled value after returning to active mode in ADC10_ISR
+#else
+ // no ADC
+ return 0;
+#endif
+}
+
+__attribute__((interrupt(ADC10_VECTOR)))
+void ADC10_ISR(void)
+{
+#if defined(__MSP430_HAS_ADC10)
+ __bic_SR_register_on_exit(CPUOFF); // return to active mode
+#endif
+
+#if defined(__MSP430_HAS_ADC10_B__)
+
+ switch(ADC10IV,12) {
+ case 0: break; // No interrupt
+ case 2: break; // conversion result overflow
+ case 4: break; // conversion time overflow
+ case 6: break; // ADC10HI
+ case 8: break; // ADC10LO
+ case 10: break; // ADC10IN
+ case 12:
+ __bic_SR_register_on_exit(CPUOFF); // return to active mode
+ break; // Clear CPUOFF bit from 0(SR)
+ default: break;
+ }
+
+ ADC10IFG = 0; // Clear Flags
+#endif
+}
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