refactor checkpoint: splitting MCU-specific code into arch/$MCU.[ch]

Phew, that's a lot of changes!  And there's still a lot more to do...

10 files changed, 47 insertions, 366 deletions

diff --git a/fsm/adc.c b/fsm/adc.c
index 31b250f..6d4eeb1 100644
--- a/fsm/adc.c
+++ b/fsm/adc.c
@@ -16,57 +16,14 @@
 
 
 static inline void set_admux_therm() {
-    #if (ATTINY == 1634)
-        ADMUX = ADMUX_THERM;
-    #elif (ATTINY == 25) || (ATTINY == 45) || (ATTINY == 85)
-        ADMUX = ADMUX_THERM | (1 << ADLAR);
-    #elif (ATTINY == 841)  // FIXME: not tested
-        ADMUXA = ADMUXA_THERM;
-        ADMUXB = ADMUXB_THERM;
-    #elif defined(AVRXMEGA3)  // ATTINY816, 817, etc
-        ADC0.MUXPOS = ADC_MUXPOS_TEMPSENSE_gc;  // read temperature
-        ADC0.CTRLC = ADC_SAMPCAP_bm | ADC_PRESC_DIV64_gc | ADC_REFSEL_INTREF_gc; // Internal ADC reference
-    #else
-        #error Unrecognized MCU type
-    #endif
+    hwdef_set_admux_therm();
     adc_channel = 1;
     adc_sample_count = 0;  // first result is unstable
     ADC_start_measurement();
 }
 
 inline void set_admux_voltage() {
-    #if (ATTINY == 1634)
-        #ifdef USE_VOLTAGE_DIVIDER // 1.1V / pin7
-            ADMUX = ADMUX_VOLTAGE_DIVIDER;
-        #else  // VCC / 1.1V reference
-            ADMUX = ADMUX_VCC;
-        #endif
-    #elif (ATTINY == 25) || (ATTINY == 45) || (ATTINY == 85)
-        #ifdef USE_VOLTAGE_DIVIDER  // 1.1V / pin7
-            ADMUX = ADMUX_VOLTAGE_DIVIDER | (1 << ADLAR);
-        #else  // VCC / 1.1V reference
-            ADMUX = ADMUX_VCC | (1 << ADLAR);
-        #endif
-    #elif (ATTINY == 841)  // FIXME: not tested
-        #ifdef USE_VOLTAGE_DIVIDER  // 1.1V / pin7
-            ADMUXA = ADMUXA_VOLTAGE_DIVIDER;
-            ADMUXB = ADMUXB_VOLTAGE_DIVIDER;
-        #else  // VCC / 1.1V reference
-            ADMUXA = ADMUXA_VCC;
-            ADMUXB = ADMUXB_VCC;
-        #endif
-    #elif defined(AVRXMEGA3)  // ATTINY816, 817, etc
-        #ifdef USE_VOLTAGE_DIVIDER  // 1.1V / ADC input pin
-            // verify that this is correct!!!  untested
-            ADC0.MUXPOS = ADMUX_VOLTAGE_DIVIDER;  // read the requested ADC pin
-            ADC0.CTRLC = ADC_SAMPCAP_bm | ADC_PRESC_DIV64_gc | ADC_REFSEL_INTREF_gc; // Use internal ADC reference
-        #else  // VCC / 1.1V reference
-            ADC0.MUXPOS = ADC_MUXPOS_INTREF_gc;  // read internal reference
-            ADC0.CTRLC = ADC_SAMPCAP_bm | ADC_PRESC_DIV64_gc | ADC_REFSEL_VDDREF_gc; // Vdd (Vcc) be ADC reference
-        #endif
-    #else
-        #error Unrecognized MCU type
-    #endif
+    hwdef_set_admux_voltage();
     adc_channel = 0;
     adc_sample_count = 0;  // first result is unstable
     ADC_start_measurement();
@@ -74,79 +31,19 @@ inline void set_admux_voltage() {
 
 
 #ifdef TICK_DURING_STANDBY
-inline void adc_sleep_mode() {
     // needs a special sleep mode to get accurate measurements quickly 
     // ... full power-down ends up using more power overall, and causes 
     // some weird issues when the MCU doesn't stay awake enough cycles 
     // to complete a reading
-    #ifdef SLEEP_MODE_ADC
-        // attiny1634
-        set_sleep_mode(SLEEP_MODE_ADC);
-    #elif defined(AVRXMEGA3)  // ATTINY816, 817, etc
-        set_sleep_mode(SLEEP_MODE_STANDBY);
-    #else
-        #error No ADC sleep mode defined for this hardware.
-    #endif
-}
+    #define adc_sleep_mode  mcu_adc_sleep_mode
 #endif
 
-inline void ADC_start_measurement() {
-    #if (ATTINY == 25) || (ATTINY == 45) || (ATTINY == 85) || (ATTINY == 841) || (ATTINY == 1634)
-        ADCSRA |= (1 << ADSC) | (1 << ADIE);
-    #elif defined(AVRXMEGA3)  // ATTINY816, 817, etc
-        ADC0.INTCTRL |= ADC_RESRDY_bm; // enable interrupt
-        ADC0.COMMAND |= ADC_STCONV_bm; // Start the ADC conversions
-    #else
-        #error unrecognized MCU type
-    #endif
-}
+#define ADC_start_measurement  mcu_adc_start_measurement
 
 // set up ADC for reading battery voltage
-inline void ADC_on()
-{
-    #if (ATTINY == 25) || (ATTINY == 45) || (ATTINY == 85) || (ATTINY == 1634)
-        set_admux_voltage();
-        #ifdef USE_VOLTAGE_DIVIDER
-            // disable digital input on divider pin to reduce power consumption
-            VOLTAGE_ADC_DIDR |= (1 << VOLTAGE_ADC);
-        #else
-            // disable digital input on VCC pin to reduce power consumption
-            //VOLTAGE_ADC_DIDR |= (1 << VOLTAGE_ADC);  // FIXME: unsure how to handle for VCC pin
-        #endif
-        #if (ATTINY == 1634)
-            //ACSRA |= (1 << ACD);  // turn off analog comparator to save power
-            ADCSRB |= (1 << ADLAR);  // left-adjust flag is here instead of ADMUX
-        #endif
-        // enable, start, auto-retrigger, prescale
-        ADCSRA = (1 << ADEN) | (1 << ADSC) | (1 << ADATE) | ADC_PRSCL;
-        // end tiny25/45/85
-    #elif (ATTINY == 841)  // FIXME: not tested, missing left-adjust
-        ADCSRB = 0;  // Right adjusted, auto trigger bits cleared.
-        //ADCSRA = (1 << ADEN ) | 0b011;  // ADC on, prescaler division factor 8.
-        set_admux_voltage();
-        // enable, start, auto-retrigger, prescale
-        ADCSRA = (1 << ADEN) | (1 << ADSC) | (1 << ADATE) | ADC_PRSCL;
-        //ADCSRA |= (1 << ADSC);  // start measuring
-    #elif defined(AVRXMEGA3)  // ATTINY816, 817, etc
-        VREF.CTRLA |= VREF_ADC0REFSEL_1V1_gc; // Set Vbg ref to 1.1V
-        // Enabled, free-running (aka, auto-retrigger), run in standby
-        ADC0.CTRLA = ADC_ENABLE_bm | ADC_FREERUN_bm | ADC_RUNSTBY_bm;
-        // set a INITDLY value because the AVR manual says so (section 30.3.5)
-        // (delay 1st reading until Vref is stable)
-        ADC0.CTRLD |= ADC_INITDLY_DLY16_gc;
-        set_admux_voltage();
-    #else
-        #error Unrecognized MCU type
-    #endif
-}
-
-inline void ADC_off() {
-    #ifdef AVRXMEGA3  // ATTINY816, 817, etc
-        ADC0.CTRLA &= ~(ADC_ENABLE_bm);  // disable the ADC
-    #else
-        ADCSRA &= ~(1<<ADEN); //ADC off
-    #endif
-}
+#define ADC_on   mcu_adc_on
+// stop the ADC
+#define ADC_off  mcu_adc_off
 
 #ifdef USE_VOLTAGE_DIVIDER
 static inline uint8_t calc_voltage_divider(uint16_t value) {
@@ -171,15 +68,11 @@ static inline uint8_t calc_voltage_divider(uint16_t value) {
 #define ADC_CYCLES_PER_SECOND 2
 #endif
 
-#ifdef AVRXMEGA3  // ATTINY816, 817, etc
-#define ADC_vect ADC0_RESRDY_vect
-#endif
 // happens every time the ADC sampler finishes a measurement
 ISR(ADC_vect) {
 
-    #ifdef AVRXMEGA3  // ATTINY816, 817, etc
-    ADC0.INTFLAGS = ADC_RESRDY_bm; // clear the interrupt
-    #endif
+    // clear the interrupt flag
+    mcu_adc_vect_clear();
 
     if (adc_sample_count) {
 
@@ -188,22 +81,12 @@ ISR(ADC_vect) {
         uint8_t channel = adc_channel;
 
         // update the latest value
-        #ifdef AVRXMEGA3  // ATTINY816, 817, etc
-        // Use the factory calibrated values in SIGROW.TEMPSENSE0 and SIGROW.TEMPSENSE1
-        // to calculate a temperature reading in Kelvin, then left-align it. 
-        if (channel == 1) { // thermal, convert ADC reading to left-aligned Kelvin
-            int8_t sigrow_offset = SIGROW.TEMPSENSE1; // Read signed value from signature row
-            uint8_t sigrow_gain = SIGROW.TEMPSENSE0; // Read unsigned value from signature row
-            uint32_t temp = ADC0.RES - sigrow_offset;
-            temp *= sigrow_gain; // Result might overflow 16 bit variable (10bit+8bit)
-            temp += 0x80; // Add 1/2 to get correct rounding on division below
-            temp >>= 8; // Divide result to get Kelvin
-            m = (temp << 6); // left align it
-        }
-        else { m = (ADC0.RES << 6); } // voltage, force left-alignment
-
+        #ifdef MCU_ADC_RESULT_PER_TYPE
+            // thermal, convert ADC reading to left-aligned Kelvin
+            if (channel) m = mcu_adc_result_temp();
+            else m = mcu_adc_result_volts();
         #else
-        m = ADC;
+            m = mcu_adc_result();
         #endif
         adc_raw[channel] = m;
 
@@ -235,11 +118,7 @@ void adc_deferred() {
     // real-world entropy makes this a true random, not pseudo
     // Why here instead of the ISR?  Because it makes the time-critical ISR
     // code a few cycles faster and we don't need crypto-grade randomness.
-    #ifdef AVRXMEGA3  // ATTINY816, 817, etc
-    pseudo_rand_seed += ADC0.RESL; // right aligned, not left... so should be equivalent?
-    #else
-    pseudo_rand_seed += (ADCL >> 6) + (ADCH << 2);
-    #endif
+    pseudo_rand_seed += mcu_adc_lsb();
     #endif
 
     // the ADC triggers repeatedly when it's on, but we only need to run the
@@ -373,9 +252,9 @@ static inline void ADC_voltage_handler() {
     if (lvp_timer) {
         lvp_timer --;
     } else {  // it has been long enough since the last warning
-    	#ifdef DUAL_VOLTAGE_FLOOR
-    	if (((voltage < VOLTAGE_LOW) && (voltage > DUAL_VOLTAGE_FLOOR)) || (voltage < DUAL_VOLTAGE_LOW_LOW)) {
-    	#else
+        #ifdef DUAL_VOLTAGE_FLOOR
+        if (((voltage < VOLTAGE_LOW) && (voltage > DUAL_VOLTAGE_FLOOR)) || (voltage < DUAL_VOLTAGE_LOW_LOW)) {
+        #else
         if (voltage < VOLTAGE_LOW) {
         #endif
             // send out a warning
@@ -440,6 +319,8 @@ static inline void ADC_temperature_handler() {
 
     // let the UI see the current temperature in C
     // Convert ADC units to Celsius (ish)
+    // FIXME: call something in arch/$mcu.h or hwdef.h
+    //        instead of calculating this here
     #ifndef USE_EXTERNAL_TEMP_SENSOR
     // onboard sensor for attiny25/45/85/1634
     temperature = (measurement>>1) + THERM_CAL_OFFSET + (int16_t)TH_CAL - 275;
diff --git a/fsm/adc.h b/fsm/adc.h
index 1bb67ed..e4046a4 100644
--- a/fsm/adc.h
+++ b/fsm/adc.h
@@ -102,11 +102,15 @@ static inline void ADC_temperature_handler();
 #endif  // ifdef USE_THERMAL_REGULATION
 
 
-inline void ADC_on();
-inline void ADC_off();
-inline void ADC_start_measurement();
+//inline void ADC_on();
+#define ADC_on   mcu_adc_on
+//inline void ADC_off();
+#define ADC_off  mcu_adc_off
+//inline void ADC_start_measurement();
+#define ADC_start_measurement  mcu_adc_start_measurement
 
 #ifdef TICK_DURING_STANDBY
-inline void adc_sleep_mode();
+    //inline void adc_sleep_mode();
+    #define adc_sleep_mode  mcu_adc_sleep_mode
 #endif
 
diff --git a/fsm/main.c b/fsm/main.c
index 0524115..1c01878 100644
--- a/fsm/main.c
+++ b/fsm/main.c
@@ -23,66 +23,6 @@ ISR(TIMER1_COMPA_vect) {
 }
 #endif
 
-// FIXME: hw_setup() shouldn't be here ... move it entirely to hwdef files
-#if (ATTINY == 25) || (ATTINY == 45) || (ATTINY == 85)
-static inline void hw_setup() {
-    #if !defined(USE_GENERIC_HWDEF_SETUP)
-        hwdef_setup();
-    #else
-        // configure PWM channels
-        #if PWM_CHANNELS >= 1
-            DDRB |= (1 << PWM1_PIN);
-            TCCR0B = 0x01; // pre-scaler for timer (1 => 1, 2 => 8, 3 => 64...)
-            TCCR0A = PHASE;
-            #if (PWM1_PIN == PB4) // Second PWM counter is ... weird
-                TCCR1 = _BV (CS10);
-                GTCCR = _BV (COM1B1) | _BV (PWM1B);
-                OCR1C = 255;  // Set ceiling value to maximum
-            #endif
-        #endif
-        // tint ramping needs second channel enabled,
-        // despite PWM_CHANNELS being only 1
-        #if (PWM_CHANNELS >= 2) || defined(USE_TINT_RAMPING)
-            DDRB |= (1 << PWM2_PIN);
-            #if (PWM2_PIN == PB4) // Second PWM counter is ... weird
-                TCCR1 = _BV (CS10);
-                GTCCR = _BV (COM1B1) | _BV (PWM1B);
-                OCR1C = 255;  // Set ceiling value to maximum
-            #endif
-        #endif
-        #if PWM_CHANNELS >= 3
-            DDRB |= (1 << PWM3_PIN);
-            #if (PWM3_PIN == PB4) // Second PWM counter is ... weird
-                TCCR1 = _BV (CS10);
-                GTCCR = _BV (COM1B1) | _BV (PWM1B);
-                OCR1C = 255;  // Set ceiling value to maximum
-            #endif
-        #endif
-        #if PWM_CHANNELS >= 4
-            // 4th PWM channel is ... not actually supported in hardware  :(
-            DDRB |= (1 << PWM4_PIN);
-            //OCR1C = 255;  // Set ceiling value to maximum
-            TCCR1 = 1<<CTC1 | 1<<PWM1A | 3<<COM1A0 | 2<<CS10;
-            GTCCR = (2<<COM1B0) | (1<<PWM1B);
-            // set up an interrupt to control PWM4 pin
-            TIMSK |= (1<<OCIE1A) | (1<<TOIE1);
-        #endif
-
-        // configure e-switch
-        PORTB = (1 << SWITCH_PIN);  // e-switch is the only input
-        PCMSK = (1 << SWITCH_PIN);  // pin change interrupt uses this pin
-    #endif  // ifdef USE_GENERIC_HWDEF_SETUP
-}
-#elif (ATTINY == 1634) || defined(AVRXMEGA3)  // ATTINY816, 817, etc
-static inline void hw_setup() {
-    // this gets tricky with so many pins...
-    // ... so punt it to the hwdef file
-    hwdef_setup();
-}
-#else
-    #error Unrecognized MCU type
-#endif
-
 
 //#ifdef USE_REBOOT
 static inline void prevent_reboot_loop() {
@@ -107,7 +47,7 @@ int main() {
     prevent_reboot_loop();
     //#endif
 
-    hw_setup();
+    hwdef_setup();
 
     #if 0
     #ifdef HALFSPEED
diff --git a/fsm/misc.c b/fsm/misc.c
index bc10ea1..5d58f52 100644
--- a/fsm/misc.c
+++ b/fsm/misc.c
@@ -288,25 +288,3 @@ uint8_t triangle_wave(uint8_t phase) {
 }
 #endif
 
-#ifdef USE_REBOOT
-void reboot() {
-    // put the WDT in hard reset mode, then trigger it
-    cli();
-    #if (ATTINY == 25) || (ATTINY == 45) || (ATTINY == 85)
-        WDTCR = 0xD8 | WDTO_15MS;
-    #elif (ATTINY == 1634)
-        // allow protected configuration changes for next 4 clock cycles
-        CCP = 0xD8;  // magic number
-        // reset (WDIF + WDE), no WDIE, fastest (16ms) timing (0000)
-        // (DS section 8.5.2 and table 8-4)
-        WDTCSR = 0b10001000;
-    #elif defined(AVRXMEGA3)  // ATTINY816, 817, etc
-        CCP = CCP_IOREG_gc;  // temporarily disable change protection
-        WDT.CTRLA = WDT_PERIOD_8CLK_gc;  // Enable, timeout 8ms
-    #endif
-    sei();
-    wdt_reset();
-    while (1) {}
-}
-#endif
-
diff --git a/fsm/misc.h b/fsm/misc.h
index 8de6b29..ba1f8d9 100644
--- a/fsm/misc.h
+++ b/fsm/misc.h
@@ -62,7 +62,3 @@ void rgb_led_set(uint8_t value);
 uint8_t triangle_wave(uint8_t phase);
 #endif
 
-#ifdef USE_REBOOT
-void reboot();
-#endif
-
diff --git a/fsm/pcint.c b/fsm/pcint.c
index 131d0c3..d00b51d 100644
--- a/fsm/pcint.c
+++ b/fsm/pcint.c
@@ -13,58 +13,8 @@ uint8_t button_is_pressed() {
     return value;
 }
 
-inline void PCINT_on() {
-    #if (ATTINY == 25) || (ATTINY == 45) || (ATTINY == 85)
-        // enable pin change interrupt
-        GIMSK |= (1 << PCIE);
-        // only pay attention to the e-switch pin
-        #if 0  // this is redundant; was already done in main()
-        PCMSK = (1 << SWITCH_PCINT);
-        #endif
-        // set bits 1:0 to 0b01 (interrupt on rising *and* falling edge) (default)
-        // MCUCR &= 0b11111101;  MCUCR |= 0b00000001;
-    #elif (ATTINY == 1634)
-        // enable pin change interrupt
-        #ifdef SWITCH2_PCIE
-        GIMSK |= ((1 << SWITCH_PCIE) | (1 << SWITCH2_PCIE));
-        #else
-        GIMSK |= (1 << SWITCH_PCIE);
-        #endif
-    #elif defined(AVRXMEGA3)  // ATTINY816, 817, etc)
-        SWITCH_ISC_REG |= PORT_ISC_BOTHEDGES_gc;
-    #else
-        #error Unrecognized MCU type
-    #endif
-}
-
-inline void PCINT_off() {
-    #if (ATTINY == 25) || (ATTINY == 45) || (ATTINY == 85)
-        // disable all pin-change interrupts
-        GIMSK &= ~(1 << PCIE);
-    #elif (ATTINY == 1634)
-        // disable all pin-change interrupts
-        GIMSK &= ~(1 << SWITCH_PCIE);
-    #elif defined(AVRXMEGA3)  // ATTINY816, 817, etc)
-        SWITCH_ISC_REG &= ~(PORT_ISC_gm);
-    #else
-        #error Unrecognized MCU type
-    #endif
-}
-
-//void button_change_interrupt() {
-#if (ATTINY == 25) || (ATTINY == 45) || (ATTINY == 85) || (ATTINY == 1634)
-    #ifdef PCINT_vect
-    ISR(PCINT_vect) {
-    #else
-    ISR(PCINT0_vect) {
-    #endif
-#elif defined(AVRXMEGA3)  // ATTINY816, 817, etc)
-    ISR(SWITCH_VECT) {
-        // Write a '1' to clear the interrupt flag
-        SWITCH_INTFLG |= (1 << SWITCH_PIN);
-#else
-    #error Unrecognized MCU type
-#endif
+ISR(SWITCH_VECT) {
+    mcu_switch_vect_clear();
 
     irq_pcint = 1;  // let deferred code know an interrupt happened
 
diff --git a/fsm/pcint.h b/fsm/pcint.h
index cd7ba02..62f93ab 100644
--- a/fsm/pcint.h
+++ b/fsm/pcint.h
@@ -9,7 +9,9 @@ volatile uint8_t irq_pcint = 0;  // pin change interrupt happened?
 #define BP_SAMPLES 32
 volatile uint8_t button_last_state;
 uint8_t button_is_pressed();
-inline void PCINT_on();
-inline void PCINT_off();
+//inline void PCINT_on();
+//inline void PCINT_off();
+#define PCINT_on   mcu_pcint_on
+#define PCINT_off  mcu_pcint_off
 void PCINT_inner(uint8_t pressed);
 
diff --git a/fsm/spaghetti-monster.h b/fsm/spaghetti-monster.h
index c035d5b..7084ad4 100644
--- a/fsm/spaghetti-monster.h
+++ b/fsm/spaghetti-monster.h
@@ -13,10 +13,9 @@
  * - ...
  */
 
-#include "arch/mcu.h"
+////////// include all the .h files //////////
 
-#include <avr/eeprom.h>
-#include <avr/power.h>
+#include "arch/mcu.h"
 
 // include project definitions to help with recognizing symbols
 #include "fsm/events.h"
@@ -39,6 +38,10 @@
 #include "arch/delay.h"
 #endif
 
+////////// include all the .c files //////////
+
+#include "arch/mcu.c"
+
 #ifdef USE_DEBUG_BLINK
 #define DEBUG_FLASH PWM1_LVL = 64; delay_4ms(2); PWM1_LVL = 0;
 void debug_blink(uint8_t num) {
diff --git a/fsm/wdt.c b/fsm/wdt.c
index 64f006e..1095d44 100644
--- a/fsm/wdt.c
+++ b/fsm/wdt.c
@@ -7,85 +7,9 @@
 #include <avr/interrupt.h>
 #include <avr/wdt.h>
 
-// *** Note for the AVRXMEGA3 (1-Series, eg 816 and 817), the WDT 
-// is not used for time-based interrupts.  A new peripheral, the 
-// Periodic Interrupt Timer ("PIT") is used for this purpose.
-
-void WDT_on()
-{
-    #if (ATTINY == 25) || (ATTINY == 45) || (ATTINY == 85)
-        // interrupt every 16ms
-        //cli();                          // Disable interrupts
-        wdt_reset();                    // Reset the WDT
-        WDTCR |= (1<<WDCE) | (1<<WDE);  // Start timed sequence
-        WDTCR = (1<<WDIE);              // Enable interrupt every 16ms
-        //sei();                          // Enable interrupts
-    #elif (ATTINY == 1634)
-        wdt_reset();                    // Reset the WDT
-        WDTCSR = (1<<WDIE);             // Enable interrupt every 16ms
-    #elif defined(AVRXMEGA3)  // ATTINY816, 817, etc
-        RTC.PITINTCTRL = RTC_PI_bm;   // enable the Periodic Interrupt
-        while (RTC.PITSTATUS > 0) {}  // make sure the register is ready to be updated
-        RTC.PITCTRLA = RTC_PERIOD_CYC512_gc | RTC_PITEN_bm; // Period = 16ms, enable the PI Timer
-    #else
-        #error Unrecognized MCU type
-    #endif
-}
-
-#ifdef TICK_DURING_STANDBY
-inline void WDT_slow()
-{
-    #if (ATTINY == 25) || (ATTINY == 45) || (ATTINY == 85)
-        // interrupt slower
-        //cli();                          // Disable interrupts
-        wdt_reset();                    // Reset the WDT
-        WDTCR |= (1<<WDCE) | (1<<WDE);  // Start timed sequence
-        WDTCR = (1<<WDIE) | STANDBY_TICK_SPEED; // Enable interrupt every so often
-        //sei();                          // Enable interrupts
-    #elif (ATTINY == 1634)
-        wdt_reset();                    // Reset the WDT
-        WDTCSR = (1<<WDIE) | STANDBY_TICK_SPEED;
-    #elif defined(AVRXMEGA3)  // ATTINY816, 817, etc
-        RTC.PITINTCTRL = RTC_PI_bm;   // enable the Periodic Interrupt
-        while (RTC.PITSTATUS > 0) {}  // make sure the register is ready to be updated
-        RTC.PITCTRLA = (1<<6) | (STANDBY_TICK_SPEED<<3) | RTC_PITEN_bm; // Set period, enable the PI Timer
-    #else
-        #error Unrecognized MCU type
-    #endif
-}
-#endif
-
-inline void WDT_off()
-{
-    #if (ATTINY == 25) || (ATTINY == 45) || (ATTINY == 85)
-        //cli();                          // Disable interrupts
-        wdt_reset();                    // Reset the WDT
-        MCUSR &= ~(1<<WDRF);            // Clear Watchdog reset flag
-        WDTCR |= (1<<WDCE) | (1<<WDE);  // Start timed sequence
-        WDTCR = 0x00;                   // Disable WDT
-        //sei();                          // Enable interrupts
-    #elif (ATTINY == 1634)
-        cli();                // needed because CCP, below
-        wdt_reset();          // Reset the WDT
-        MCUSR &= ~(1<<WDRF);  // clear watchdog reset flag
-        CCP = 0xD8;           // enable config changes
-        WDTCSR = 0;           // disable and clear all WDT settings
-        sei();
-    #elif defined(AVRXMEGA3)  // ATTINY816, 817, etc
-        while (RTC.PITSTATUS > 0) {}  // make sure the register is ready to be updated
-        RTC.PITCTRLA = 0; // Disable the PI Timer
-    #else
-        #error Unrecognized MCU type
-    #endif
-}
-
 // clock tick -- this runs every 16ms (62.5 fps)
-#ifdef AVRXMEGA3  // ATTINY816, 817, etc
-ISR(RTC_PIT_vect) {
-    RTC.PITINTFLAGS = RTC_PI_bm; // clear the PIT interrupt flag 
-#else
 ISR(WDT_vect) {
-#endif
+    mcu_wdt_vect_clear();
     irq_wdt = 1;  // WDT event happened
 }
 
diff --git a/fsm/wdt.h b/fsm/wdt.h
index abf34c5..98eaf25 100644
--- a/fsm/wdt.h
+++ b/fsm/wdt.h
@@ -6,8 +6,11 @@
 
 #define TICKS_PER_SECOND 62
 
-void WDT_on();
-inline void WDT_off();
+//void WDT_on();
+//inline void WDT_off();
+#define WDT_on    mcu_wdt_active
+#define WDT_slow  mcu_wdt_standby
+#define WDT_off   mcu_wdt_stop
 
 volatile uint8_t irq_wdt = 0;  // WDT interrupt happened?