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Diffstat (limited to 'arch/avr32dd20.c')
| -rw-r--r-- | arch/avr32dd20.c | 264 |
1 files changed, 264 insertions, 0 deletions
diff --git a/arch/avr32dd20.c b/arch/avr32dd20.c new file mode 100644 index 0000000..2ac3526 --- /dev/null +++ b/arch/avr32dd20.c @@ -0,0 +1,264 @@ +// arch/avr32dd20.h: avr32dd20 support functions +// Copyright (C) 2023 Selene ToyKeeper +// SPDX-License-Identifier: GPL-3.0-or-later +#pragma once + +#include "arch/avr32dd20.h" + +////////// clock speed / delay stuff ////////// + +inline void mcu_clock_speed() { + // TODO: allow hwdef to define a base clock speed + // run the internal clock at 12 MHz, not the default 4 MHz + _PROTECTED_WRITE( CLKCTRL.OSCHFCTRLA, + CLKCTRL_FRQSEL_12M_gc | CLKCTRL_AUTOTUNE_bm ); + // (another option is to use 20 MHz / 2, like attiny1616 does) + // divide 20 MHz to run at 10 MHz to match attiny1616 + //_PROTECTED_WRITE( CLKCTRL.MCLKCTRLB, + // CLKCTRL_PDIV_2X_gc | CLKCTRL_PEN_bm ); +} + +///// clock dividers +// this should work, but needs further validation +inline void clock_prescale_set(uint8_t n) { + cli(); + _PROTECTED_WRITE(CLKCTRL.MCLKCTRLB, n); // Set the prescaler + while (CLKCTRL.MCLKSTATUS & CLKCTRL_SOSC_bm) {} // wait for clock change to finish + sei(); +} + + +////////// ADC voltage / temperature ////////// + +// ADC0.CTRLA bits: +// RUNSTDBY, -, CONVMODE, LEFTADJ, RESSEL[1:0], FREERUN, ENABLE +// CTRLB bits: -, -, -, -, -, SAMPNUM[2:0] +// CTRLC bits: -, -, -, -, PRESC[3:0] +// CTRLD bits: INITDLY[2:0], -, SAMPDLY[3:0] +// CTRLE bits: -, -, -, -, -, WINCM[2:0] +// SAMPCTRL: 8 bits +// MUXPOS, MUXNEG: 7 bits each +// COMMAND: -, -, -, -, -, -, SPCONV, STCONV + +inline void mcu_set_admux_therm() { + // ADC init: Datasheet section 33.3.2 + // Temperature mode: Datasheet section 33.3.3.8 + // measurements should be 12-bit right-adjusted single-ended conversion + // set Vref to 2.048V for temperature mode + VREF.ADC0REF = VREF_REFSEL_2V048_gc; + // set temp sensor as input + ADC0.MUXPOS = ADC_MUXPOS_TEMPSENSE_gc; + // configure init delay to >= 25 us * Fclk_adc (no sample delay needed) + ADC0.CTRLD = ADC_INITDLY_DLY32_gc | ADC_SAMPDLY_DLY0_gc; + // configure ADC sample length to >= 28 us * Fclk_adc + ADC0.SAMPCTRL = 32; + // set single-ended or differential + // set resolution to 12 bits + // set left- or right-adjust + // set free-running mode or not (yes) + ADC0.CTRLA = ADC_CONVMODE_SINGLEENDED_gc + | ADC_RESSEL_12BIT_gc + | ADC_LEFTADJ_bm + | ADC_FREERUN_bm; + // set number of samples (requires adjustment in formula too) + ADC0.CTRLB = ADC_SAMPNUM_NONE_gc; + // accumulate more samples for more resolution + ADC0.CTRLB = ADC_SAMPNUM_ACC16_gc; // 16 samples per result + // set a clock prescaler + //ADC0.CTRLC = ADC_PRESC_DIV64_gc; // use this when no accumulation + ADC0.CTRLC = ADC_PRESC_DIV4_gc; // measure faster when oversampling + // enable the ADC + ADC0.CTRLA |= ADC_ENABLE_bm; + // actually start measuring (happens in another function) + //ADC0.COMMAND |= ADC_STCONV_bm; + // for each measurement: + // process according to sigrow data + formula +} + +inline void mcu_set_admux_voltage() { + // ADC init: Datasheet section 33.3.2 + // set Vref + VREF.ADC0REF = VREF_REFSEL_1V024_gc; + // set single-ended or differential + // set resolution to 12 bits + // set left- or right-adjust (right) + // set free-running mode or not (yes) + ADC0.CTRLA = ADC_CONVMODE_SINGLEENDED_gc + | ADC_RESSEL_12BIT_gc + | ADC_LEFTADJ_bm // has no effect when 16+ samples taken + | ADC_FREERUN_bm + | ADC_RUNSTBY_bm // allow voltage sense in standby mode + ; + // set number of samples + ADC0.CTRLB = ADC_SAMPNUM_ACC16_gc; // 16 samples per result + // set a clock prescaler + ADC0.CTRLC = ADC_PRESC_DIV4_gc; // measure faster when oversampling + // select the positive ADC input with MUXPOS + #ifdef USE_VOLTAGE_DIVIDER // external voltage divider + // ADC input pin / Vref + ADC0.MUXPOS = ADMUX_VOLTAGE_DIVIDER; // external pin + #elif defined (USE_VOLTAGE_VDDIO2) // internal voltage divider + // (Vbat / 10) / Vref + ADC0.MUXPOS = ADC_MUXPOS_VDDIO2DIV10_gc; + #else // measure directly on VDD/VCC pin + // (Vbat / 10) / Vref + ADC0.MUXPOS = ADC_MUXPOS_VDDDIV10_gc; + #endif + // enable the ADC + ADC0.CTRLA |= ADC_ENABLE_bm; + // actually start measuring (happens in another function) + //ADC0.COMMAND |= ADC_STCONV_bm; +} + +inline void mcu_adc_sleep_mode() { + set_sleep_mode(SLEEP_MODE_STANDBY); +} + +inline void mcu_adc_start_measurement() { + ADC0.INTCTRL |= ADC_RESRDY_bm; // enable interrupt + ADC0.COMMAND |= ADC_STCONV_bm; // actually start measuring +} + +/* +void mcu_adc_on() { + hwdef_set_admux_voltage(); + mcu_adc_start_measurement(); +} +*/ + +inline void mcu_adc_off() { + ADC0.CTRLA &= ~(ADC_ENABLE_bm); // disable the ADC +} + +inline void mcu_adc_vect_clear() { + ADC0.INTFLAGS = ADC_RESRDY_bm; // clear the interrupt +} + +inline uint16_t mcu_adc_result() { + // value is 12-bit left-aligned + 16x oversampling = 16 bits total + return ADC0.RES; +} + +inline uint8_t mcu_vdd_raw2cooked(uint16_t measurement) { + // In : 65535 * (Vbat / 10) / 1.024V + // Out: uint8_t: Vbat * 40 + // (add 80 to round up near a boundary) + uint8_t vbat40 = (uint16_t)(measurement + 80) / 160; + return vbat40; +} + +#if 0 +inline uint16_t mcu_vdd_raw2fine(uint16_t measurement) { + // In : 65535 * (Vbat / 10) / 1.024V + // Out: 65535 * (Vbat / 10) / 1.024V + // This MCU's native format is already correct + return measurement; +} +#endif + +inline uint16_t mcu_temp_raw2cooked(uint16_t measurement) { + // convert raw ADC values to calibrated temperature + // In: ADC raw temperature (16-bit, or 12-bit left-aligned) + // Out: Kelvin << 6 + // Precision: 1/64th Kelvin (but noisy) + // AVR DD datasheet section 33.3.3.8 + uint16_t sigrow_slope = SIGROW.TEMPSENSE0; // factory calibration data + uint16_t sigrow_offset = SIGROW.TEMPSENSE1; // 12-bit value + //const uint32_t scaling_factor = 4096; // use top 12 bits of ADC data + //uint32_t temp = sigrow_offset - (measurement >> 4); + const uint32_t scaling_factor = 65536; // use all 16 bits of ADC data + uint32_t temp = (sigrow_offset << 4) - measurement; + temp *= sigrow_slope; // 24-bit result + temp += scaling_factor / 8; // Add 1/8th K to get correct rounding on later divisions + //temp = temp >> 6; // change (K << 12) to (K << 6) + temp = temp >> 10; // change (K << 16) to (K << 6) + return temp; // left-aligned uint16_t, 0 to 1023.98 Kelvin +} + +inline uint8_t mcu_adc_lsb() { + // volts and temp are both 16-bit, so the LSB is useful as-is + return ADC0_RESL; +} + + +////////// WDT ////////// +// this uses the RTC PIT interrupt instead of WDT, +// as recommended on AVR 0/1-series and later: +// https://github.com/SpenceKonde/DxCore/blob/master/megaavr/extras/PowerSave.md#using-the-real-time-counter-rtcpit +// The PIT runs even in power-down mode, unlike RTC, +// and its cycles are relative to the AVR's internal 32768 Hz ULP oscillator +// AVR datasheet sections 26, 26.5, 26.9, 26.12, 26.13.12 + +// PIT tick speeds: +// 0 (none) +// 1 8192 Hz (CYC4) +// 2 4096 Hz +// 3 2048 Hz +// 4 1024 Hz (CYC32) +// 5 512 Hz +// 6 256 Hz +// 7 128 Hz +// 8 64 Hz (default) (CYC512) +inline void mcu_wdt_active() { + RTC.PITINTCTRL = RTC_PI_bm; // enable the Periodic Interrupt + while (RTC.PITSTATUS > 0) {} // make sure the register is ready to be updated + // Period = 16ms (64 Hz), enable the PI Timer + RTC.PITCTRLA = RTC_PERIOD_CYC512_gc | RTC_PITEN_bm; +} + +// STANDBY_TICK_SPEED: +// 0 64 Hz +// 1 32 Hz +// 2 16 Hz +// 3 8 Hz (default) +// 4 4 Hz +// 5 2 Hz +// 6 1 Hz +inline void mcu_wdt_standby() { + RTC.PITINTCTRL = RTC_PI_bm; // enable the Periodic Interrupt + while (RTC.PITSTATUS > 0) {} // make sure the register is ready to be updated + // Set period (64 Hz / STANDBY_TICK_SPEED = 8 Hz), enable the PI Timer + RTC.PITCTRLA = ((8+STANDBY_TICK_SPEED)<<3) | RTC_PITEN_bm; +} + +inline void mcu_wdt_stop() { + while (RTC.PITSTATUS > 0) {} // make sure the register is ready to be updated + RTC.PITCTRLA = 0; // Disable the PI Timer +} + +inline void mcu_wdt_vect_clear() { + RTC.PITINTFLAGS = RTC_PI_bm; // clear the PIT interrupt flag +} + + +////////// PCINT - pin change interrupt (e-switch) ////////// + +inline void mcu_switch_vect_clear() { + // Write a '1' to clear the interrupt flag + SWITCH_INTFLG |= (1 << SWITCH_PIN); +} + +inline void mcu_pcint_on() { + SWITCH_ISC_REG |= PORT_ISC_BOTHEDGES_gc; +} + +inline void mcu_pcint_off() { + SWITCH_ISC_REG &= ~(PORT_ISC_gm); +} + + +////////// misc ////////// + +void reboot() { + // request a reboot (software reset) + _PROTECTED_WRITE(RSTCTRL.SWRR, RSTCTRL_SWRST_bm); +} + +inline void prevent_reboot_loop() { + // if previous reset was a crash (WDT time-out), + // prevent it from happening again immediately + //RSTCTRL.RSTFR &= ~(RSTCTRL_WDRF_bm); // reset wdt flag only + RSTCTRL.RSTFR = 0; // reset all reset status flags (maybe unneeded?) + wdt_disable(); // from avr/wdt.h +} + |