/* * MIT License * * Copyright (c) 2020 Joey Castillo * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to deal * in the Software without restriction, including without limitation the rights * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell * copies of the Software, and to permit persons to whom the Software is * furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included in all * copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE * SOFTWARE. */ #include "watch_private.h" #include "watch_utility.h" #include "tusb.h" void _watch_init(void) { // disable the LED pin (it may have been enabled by the bootloader) watch_disable_digital_output(GPIO(GPIO_PORTA, 20)); // RAM should be back-biased in STANDBY PM->STDBYCFG.bit.BBIASHS = 1; // Use switching regulator for lower power consumption. SUPC->VREG.bit.SEL = 1; while(!SUPC->STATUS.bit.VREGRDY); // wait for voltage regulator to become ready // check the battery voltage... watch_enable_adc(); uint16_t battery_voltage = watch_get_vcc_voltage(); watch_disable_adc(); // ...because we can enable the more efficient low power regulator if the system voltage is > 2.5V // still, enable LPEFF only if the battery voltage is comfortably above this threshold. if (battery_voltage >= 2700) { SUPC->VREG.bit.LPEFF = 1; } else { SUPC->VREG.bit.LPEFF = 0; } // set up the brownout detector (low battery warning) NVIC_DisableIRQ(SYSTEM_IRQn); NVIC_ClearPendingIRQ(SYSTEM_IRQn); NVIC_EnableIRQ(SYSTEM_IRQn); SUPC->BOD33.bit.ENABLE = 0; // BOD33 must be disabled to change its configuration SUPC->BOD33.bit.VMON = 0; // Monitor VDD in active and standby mode SUPC->BOD33.bit.ACTCFG = 1; // Enable sampling mode when active SUPC->BOD33.bit.RUNSTDBY = 1; // Enable sampling mode in standby SUPC->BOD33.bit.STDBYCFG = 1; // Run in standby SUPC->BOD33.bit.RUNBKUP = 0; // Don't run in backup mode SUPC->BOD33.bit.PSEL = 0x9; // Check battery level every second (we'll change this before entering sleep) SUPC->BOD33.bit.LEVEL = 34; // Detect brownout at 2.6V (1.445V + level * 34mV) SUPC->BOD33.bit.ACTION = 0x2; // Generate an interrupt when BOD33 is triggered SUPC->BOD33.bit.HYST = 0; // Disable hysteresis while(!SUPC->STATUS.bit.B33SRDY); // wait for BOD33 to sync // Enable interrupt on BOD33 detect SUPC->INTENSET.bit.BOD33DET = 1; SUPC->BOD33.bit.ENABLE = 1; // External wake depends on RTC; calendar is a required module. _watch_rtc_init(); // set up state btn_alarm_callback = NULL; a2_callback = NULL; a4_callback = NULL; } static inline void _watch_wait_for_entropy() { while (!hri_trng_get_INTFLAG_reg(TRNG, TRNG_INTFLAG_DATARDY)); } // this function is called by arc4random to get entropy for random number generation. int getentropy(void *buf, size_t buflen); // let's use the SAM L22's true random number generator to seed the PRNG! int getentropy(void *buf, size_t buflen) { hri_mclk_set_APBCMASK_TRNG_bit(MCLK); hri_trng_set_CTRLA_ENABLE_bit(TRNG); size_t i = 0; while(i < buflen / 4) { _watch_wait_for_entropy(); ((uint32_t *)buf)[i++] = hri_trng_read_DATA_reg(TRNG); } // but what if they asked for an awkward number of bytes? if (buflen % 4) { // all good: let's fill in one, two or three bytes at the end of the buffer. _watch_wait_for_entropy(); uint32_t last_little_bit = hri_trng_read_DATA_reg(TRNG); for(size_t j = 0; j <= (buflen % 4); j++) { ((uint8_t *)buf)[i * 4 + j] = (last_little_bit >> (j * 8)) & 0xFF; } } hri_trng_clear_CTRLA_ENABLE_bit(TRNG); hri_mclk_clear_APBCMASK_TRNG_bit(MCLK); return 0; } void _watch_enable_tcc(void) { // clock TCC0 with the main clock (8 MHz) and enable the peripheral clock. hri_gclk_write_PCHCTRL_reg(GCLK, TCC0_GCLK_ID, GCLK_PCHCTRL_GEN_GCLK0_Val | GCLK_PCHCTRL_CHEN); hri_mclk_set_APBCMASK_TCC0_bit(MCLK); // disable and reset TCC0. hri_tcc_clear_CTRLA_ENABLE_bit(TCC0); hri_tcc_wait_for_sync(TCC0, TCC_SYNCBUSY_ENABLE); hri_tcc_write_CTRLA_reg(TCC0, TCC_CTRLA_SWRST); hri_tcc_wait_for_sync(TCC0, TCC_SYNCBUSY_SWRST); // divide the clock down to 1 MHz if (hri_usbdevice_get_CTRLA_ENABLE_bit(USB)) { // if USB is enabled, we are running an 8 MHz clock. hri_tcc_write_CTRLA_reg(TCC0, TCC_CTRLA_PRESCALER_DIV8); } else { // otherwise it's 4 Mhz. hri_tcc_write_CTRLA_reg(TCC0, TCC_CTRLA_PRESCALER_DIV4); } // We're going to use normal PWM mode, which means period is controlled by PER, and duty cycle is controlled by // each compare channel's value: // * Buzzer tones are set by setting PER to the desired period for a given frequency, and CC[1] to half of that // period (i.e. a square wave with a 50% duty cycle). // * LEDs on CC[2] and CC[3] can be set to any value from 0 (off) to PER (fully on). hri_tcc_write_WAVE_reg(TCC0, TCC_WAVE_WAVEGEN_NPWM); #ifdef WATCH_INVERT_LED_POLARITY // This is here for the dev board, which uses a common anode LED (instead of common cathode like the actual watch). hri_tcc_set_WAVE_reg(TCC0, (1 << (TCC_WAVE_POL0_Pos + WATCH_RED_TCC_CHANNEL)) | (1 << (TCC_WAVE_POL0_Pos + WATCH_GREEN_TCC_CHANNEL))); #endif // The buzzer will set the period depending on the tone it wants to play, but we have to set some period here to // get the LED working. Almost any period will do, tho it should be below 20000 (i.e. 50 Hz) to avoid flickering. hri_tcc_write_PER_reg(TCC0, 4096); // Set the duty cycle of all pins to 0: LED's off, buzzer not buzzing. hri_tcc_write_CC_reg(TCC0, WATCH_BUZZER_TCC_CHANNEL, 0); hri_tcc_write_CC_reg(TCC0, WATCH_RED_TCC_CHANNEL, 0); hri_tcc_write_CC_reg(TCC0, WATCH_GREEN_TCC_CHANNEL, 0); // Enable the TCC hri_tcc_set_CTRLA_ENABLE_bit(TCC0); hri_tcc_wait_for_sync(TCC0, TCC_SYNCBUSY_ENABLE); // enable LED PWM pins (the LED driver assumes if the TCC is on, the pins are enabled) gpio_set_pin_direction(RED, GPIO_DIRECTION_OUT); gpio_set_pin_function(RED, WATCH_RED_TCC_PINMUX); gpio_set_pin_direction(GREEN, GPIO_DIRECTION_OUT); gpio_set_pin_function(GREEN, WATCH_GREEN_TCC_PINMUX); } void _watch_disable_tcc(void) { // disable all PWM pins gpio_set_pin_direction(BUZZER, GPIO_DIRECTION_OFF); gpio_set_pin_function(BUZZER, GPIO_PIN_FUNCTION_OFF); gpio_set_pin_direction(RED, GPIO_DIRECTION_OFF); gpio_set_pin_function(RED, GPIO_PIN_FUNCTION_OFF); gpio_set_pin_direction(GREEN, GPIO_DIRECTION_OFF); gpio_set_pin_function(GREEN, GPIO_PIN_FUNCTION_OFF); // disable the TCC hri_tcc_clear_CTRLA_ENABLE_bit(TCC0); hri_mclk_clear_APBCMASK_TCC0_bit(MCLK); } void _watch_enable_usb(void) { // disable USB, just in case. hri_usb_clear_CTRLA_ENABLE_bit(USB); // bump clock up to 8 MHz hri_oscctrl_write_OSC16MCTRL_FSEL_bf(OSCCTRL, OSCCTRL_OSC16MCTRL_FSEL_8_Val); // reset flags and disable DFLL OSCCTRL->INTFLAG.reg = OSCCTRL_INTFLAG_DFLLRDY; OSCCTRL->DFLLCTRL.reg = 0; while (!(OSCCTRL->STATUS.reg & OSCCTRL_STATUS_DFLLRDY)); // set the coarse and fine values to speed up frequency lock. uint32_t coarse =(*((uint32_t *)NVMCTRL_OTP5)) >> 26; OSCCTRL->DFLLVAL.reg = OSCCTRL_DFLLVAL_COARSE(coarse) | OSCCTRL_DFLLVAL_FINE(0x200); // set coarse and fine steps, and multiplier (48 MHz = 32768 Hz * 1465) OSCCTRL->DFLLMUL.reg = OSCCTRL_DFLLMUL_CSTEP( 1 ) | OSCCTRL_DFLLMUL_FSTEP( 1 ) | OSCCTRL_DFLLMUL_MUL( 1465 ); // set closed loop mode, chill cycle disable and USB clock recovery mode, and enable the DFLL. OSCCTRL->DFLLCTRL.reg = OSCCTRL_DFLLCTRL_MODE | OSCCTRL_DFLLCTRL_CCDIS | OSCCTRL_DFLLCTRL_ONDEMAND | OSCCTRL_DFLLCTRL_RUNSTDBY | OSCCTRL_DFLLCTRL_USBCRM | OSCCTRL_DFLLCTRL_ENABLE; while (!(OSCCTRL->STATUS.reg & OSCCTRL_STATUS_DFLLRDY)); // assign DFLL to GCLK1 GCLK->GENCTRL[1].reg = GCLK_GENCTRL_SRC(GCLK_GENCTRL_SRC_DFLL48M) | GCLK_GENCTRL_DIV(1) | GCLK_GENCTRL_GENEN;// | GCLK_GENCTRL_OE; while (GCLK->SYNCBUSY.bit.GENCTRL1); // wait for generator control 1 to sync // assign GCLK1 to USB hri_gclk_write_PCHCTRL_reg(GCLK, USB_GCLK_ID, GCLK_PCHCTRL_GEN_GCLK1_Val | GCLK_PCHCTRL_CHEN); hri_mclk_set_AHBMASK_USB_bit(MCLK); hri_mclk_set_APBBMASK_USB_bit(MCLK); // USB Pin Init gpio_set_pin_direction(PIN_PA24, GPIO_DIRECTION_OUT); gpio_set_pin_level(PIN_PA24, false); gpio_set_pin_pull_mode(PIN_PA24, GPIO_PULL_OFF); gpio_set_pin_direction(PIN_PA25, GPIO_DIRECTION_OUT); gpio_set_pin_level(PIN_PA25, false); gpio_set_pin_pull_mode(PIN_PA25, GPIO_PULL_OFF); gpio_set_pin_function(PIN_PA24, PINMUX_PA24G_USB_DM); gpio_set_pin_function(PIN_PA25, PINMUX_PA25G_USB_DP); // before we init TinyUSB, we are going to need a periodic callback to handle TinyUSB tasks. // TC2 and TC3 are reserved for devices on the 9-pin connector, so let's use TC0. // clock TC0 with the 8 MHz clock on GCLK0. hri_gclk_write_PCHCTRL_reg(GCLK, TC0_GCLK_ID, GCLK_PCHCTRL_GEN_GCLK0_Val | GCLK_PCHCTRL_CHEN); // and enable the peripheral clock. hri_mclk_set_APBCMASK_TC0_bit(MCLK); // disable and reset TC0. hri_tc_clear_CTRLA_ENABLE_bit(TC0); hri_tc_wait_for_sync(TC0, TC_SYNCBUSY_ENABLE); hri_tc_write_CTRLA_reg(TC0, TC_CTRLA_SWRST); hri_tc_wait_for_sync(TC0, TC_SYNCBUSY_SWRST); // configure the TC to overflow 1,000 times per second hri_tc_write_CTRLA_reg(TC0, TC_CTRLA_PRESCALER_DIV64 | // divide the 8 MHz clock by 64 to count at 125 KHz TC_CTRLA_MODE_COUNT8 | // count in 8-bit mode TC_CTRLA_RUNSTDBY); // run in standby, just in case we figure that out hri_tccount8_write_PER_reg(TC0, 125); // 125000 Hz / 125 = 1,000 Hz // set an interrupt on overflow; this will call TC0_Handler below. hri_tc_set_INTEN_OVF_bit(TC0); NVIC_ClearPendingIRQ(TC0_IRQn); NVIC_EnableIRQ (TC0_IRQn); // now we can init TinyUSB tusb_init(); // and start the timer that handles USB device tasks. hri_tc_set_CTRLA_ENABLE_bit(TC0); } // this function ends up getting called by printf to log stuff to the USB console. int _write(int file, char *ptr, int len) { (void)file; if (hri_usbdevice_get_CTRLA_ENABLE_bit(USB)) { tud_cdc_n_write(0, (void const*)ptr, len); tud_cdc_n_write_flush(0); return len; } return 0; } static char buf[256] = {0}; int _read(int file, char *ptr, int len) { (void)file; int actual_length = strlen(buf); if (actual_length) { memcpy(ptr, buf, min(len, actual_length)); return actual_length; } return 0; } void USB_Handler(void) { tud_int_handler(0); } static void cdc_task(void) { if (tud_cdc_n_available(0)) { tud_cdc_n_read(0, buf, sizeof(buf)); } else { memset(buf, 0, 256); } } void TC0_Handler(void) { tud_task(); cdc_task(); TC0->COUNT8.INTFLAG.reg |= TC_INTFLAG_OVF; } // USB Descriptors and tinyUSB callbacks follow. /* * The MIT License (MIT) * * Copyright (c) 2019 Ha Thach (tinyusb.org) * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to deal * in the Software without restriction, including without limitation the rights * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell * copies of the Software, and to permit persons to whom the Software is * furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included in * all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN * THE SOFTWARE. * */ //--------------------------------------------------------------------+ // Device Descriptors //--------------------------------------------------------------------+ tusb_desc_device_t const desc_device = { .bLength = sizeof(tusb_desc_device_t), .bDescriptorType = TUSB_DESC_DEVICE, .bcdUSB = 0x0200, // Use Interface Association Descriptor (IAD) for CDC // As required by USB Specs IAD's subclass must be common class (2) and protocol must be IAD (1) .bDeviceClass = TUSB_CLASS_MISC, .bDeviceSubClass = MISC_SUBCLASS_COMMON, .bDeviceProtocol = MISC_PROTOCOL_IAD, .bMaxPacketSize0 = CFG_TUD_ENDPOINT0_SIZE, .idVendor = 0x1209, .idProduct = 0x2151, .bcdDevice = 0x0100, .iManufacturer = 0x01, .iProduct = 0x02, .iSerialNumber = 0x03, .bNumConfigurations = 0x01 }; // Invoked when received GET DEVICE DESCRIPTOR // Application return pointer to descriptor uint8_t const * tud_descriptor_device_cb(void) { return (uint8_t const *) &desc_device; } //--------------------------------------------------------------------+ // Configuration Descriptor //--------------------------------------------------------------------+ enum { ITF_NUM_CDC = 0, ITF_NUM_CDC_DATA, ITF_NUM_TOTAL }; #define CONFIG_TOTAL_LEN (TUD_CONFIG_DESC_LEN + TUD_CDC_DESC_LEN) #define EPNUM_CDC_NOTIF 0x81 #define EPNUM_CDC_OUT 0x02 #define EPNUM_CDC_IN 0x82 uint8_t const desc_fs_configuration[] = { // Config number, interface count, string index, total length, attribute, power in mA TUD_CONFIG_DESCRIPTOR(1, ITF_NUM_TOTAL, 0, CONFIG_TOTAL_LEN, TUSB_DESC_CONFIG_ATT_REMOTE_WAKEUP, 100), // Interface number, string index, EP notification address and size, EP data address (out, in) and size. TUD_CDC_DESCRIPTOR(ITF_NUM_CDC, 4, EPNUM_CDC_NOTIF, 8, EPNUM_CDC_OUT, EPNUM_CDC_IN, 64), }; // Invoked when received GET CONFIGURATION DESCRIPTOR // Application return pointer to descriptor // Descriptor contents must exist long enough for transfer to complete uint8_t const * tud_descriptor_configuration_cb(uint8_t index) { (void) index; // for multiple configurations return desc_fs_configuration; } //--------------------------------------------------------------------+ // String Descriptors //--------------------------------------------------------------------+ // array of pointer to string descriptors char const* string_desc_arr [] = { (const char[]) { 0x09, 0x04 }, // 0: is supported language is English (0x0409) "TinyUSB", // 1: Manufacturer "TinyUSB Device", // 2: Product "123456", // 3: Serials, should use chip ID "TinyUSB CDC", // 4: CDC Interface }; static uint16_t _desc_str[32]; // Invoked when received GET STRING DESCRIPTOR request // Application return pointer to descriptor, whose contents must exist long enough for transfer to complete uint16_t const* tud_descriptor_string_cb(uint8_t index, uint16_t langid) { (void) langid; uint8_t chr_count; if ( index == 0) { memcpy(&_desc_str[1], string_desc_arr[0], 2); chr_count = 1; } else { // Note: the 0xEE index string is a Microsoft OS 1.0 Descriptors. // https://docs.microsoft.com/en-us/windows-hardware/drivers/usbcon/microsoft-defined-usb-descriptors if ( !(index < sizeof(string_desc_arr)/sizeof(string_desc_arr[0])) ) return NULL; const char* str = string_desc_arr[index]; // Cap at max char chr_count = strlen(str); if ( chr_count > 31 ) chr_count = 31; // Convert ASCII string into UTF-16 for(uint8_t i=0; i