circuitpython/ports/atmel-samd/mphalport.c

#include <string.h>

#include "lib/mp-readline/readline.h"
#include "lib/utils/interrupt_char.h"
#include "py/mphal.h"
#include "py/mpstate.h"
#include "py/runtime.h"
#include "py/smallint.h"
#include "shared-bindings/microcontroller/__init__.h"
#include "shared-bindings/time/__init__.h"
#include "supervisor/shared/autoreload.h"

#include "hal/include/hal_atomic.h"
#include "hal/include/hal_delay.h"
#include "hal/include/hal_gpio.h"
#include "hal/include/hal_sleep.h"
#include "sam.h"

#include "mpconfigboard.h"
#include "mphalport.h"
#include "reset.h"
#include "tick.h"
#include "usb.h"

extern struct usart_module usart_instance;
extern uint32_t common_hal_mcu_processor_get_frequency(void);

int mp_hal_stdin_rx_chr(void) {
    for (;;) {
        #ifdef MICROPY_VM_HOOK_LOOP
            MICROPY_VM_HOOK_LOOP
        #endif
        // if (reload_requested) {
        //     return CHAR_CTRL_D;
        // }
        if (usb_bytes_available()) {
            #ifdef MICROPY_HW_LED_RX
            gpio_toggle_pin_level(MICROPY_HW_LED_RX);
            #endif
            return usb_read();
        }
    }
}

void mp_hal_stdout_tx_strn(const char *str, size_t len) {
    #ifdef MICROPY_HW_LED_TX
    gpio_toggle_pin_level(MICROPY_HW_LED_TX);
    #endif

    #ifdef CIRCUITPY_BOOT_OUTPUT_FILE
    if (boot_output_file != NULL) {
        UINT bytes_written = 0;
        f_write(boot_output_file, str, len, &bytes_written);
    }
    #endif

    usb_write(str, len);
}

void mp_hal_delay_ms(mp_uint_t delay) {
    uint64_t start_tick = ticks_ms;
    uint64_t duration = 0;
    while (duration < delay) {
        #ifdef MICROPY_VM_HOOK_LOOP
            MICROPY_VM_HOOK_LOOP
        #endif
        // Check to see if we've been CTRL-Ced by autoreload or the user.
        if(MP_STATE_VM(mp_pending_exception) == MP_OBJ_FROM_PTR(&MP_STATE_VM(mp_kbd_exception))) {
            break;
        }
        duration = (ticks_ms - start_tick);
        // TODO(tannewt): Go to sleep for a little while while we wait.
    }
}

void mp_hal_delay_us(mp_uint_t delay) {
    tick_delay(delay);
}

// Do a simple timing loop to wait for a certain number of microseconds.
// Can be used when interrupts are disabled, which makes tick_delay() unreliable.
//
// Testing done at 48 MHz on SAMD21 and 120 MHz on SAMD51, multiplication and division cancel out.
// But get the frequency just in case.
#ifdef SAMD21
#define DELAY_LOOP_ITERATIONS_PER_US ( (10U*48000000U) / common_hal_mcu_processor_get_frequency())
#endif
#ifdef SAMD51
#define DELAY_LOOP_ITERATIONS_PER_US ( (30U*120000000U) / common_hal_mcu_processor_get_frequency())
#endif

void mp_hal_delay_us_loop(uint32_t us) {
    for (uint32_t i = us*DELAY_LOOP_ITERATIONS_PER_US; i > 0; i--) {
        asm volatile("nop");
    }
}

void mp_hal_disable_all_interrupts(void) {
    common_hal_mcu_disable_interrupts();
}

void mp_hal_enable_all_interrupts(void) {
    common_hal_mcu_enable_interrupts();
}