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tdicolatdicola
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atmel-samd: Implement time.ticks_ms function using SysTick timer, add global interrupt enable/disable functions.
1 parent 011056a commit 903bc8d

5 files changed

Lines changed: 58 additions & 3 deletions

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‎atmel-samd/main.c‎

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Original file line numberDiff line numberDiff line change
@@ -316,6 +316,9 @@ void samd21_init(void) {
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board_init();
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// SysTick millisecond timer initialization.
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SysTick_Config(system_cpu_clock_get_hz() / 1000);
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// Uncomment to init PIN_PA17 for debugging.
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// struct port_config pin_conf;
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// port_get_config_defaults(&pin_conf);

‎atmel-samd/modutime.c‎

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Original file line numberDiff line numberDiff line change
@@ -64,12 +64,18 @@ STATIC mp_obj_t time_sleep_us(mp_obj_t arg) {
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}
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STATIC MP_DEFINE_CONST_FUN_OBJ_1(time_sleep_us_obj, time_sleep_us);
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STATIC mp_obj_t time_ticks_ms(void) {
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return MP_OBJ_NEW_SMALL_INT(mp_hal_ticks_ms() & MP_SMALL_INT_POSITIVE_MASK);
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}
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STATIC MP_DEFINE_CONST_FUN_OBJ_0(time_ticks_ms_obj, time_ticks_ms);
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STATIC const mp_map_elem_t time_module_globals_table[] = {
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{ MP_OBJ_NEW_QSTR(MP_QSTR___name__), MP_OBJ_NEW_QSTR(MP_QSTR_utime) },
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{ MP_OBJ_NEW_QSTR(MP_QSTR_sleep), (mp_obj_t)&time_sleep_obj },
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{ MP_OBJ_NEW_QSTR(MP_QSTR_sleep_ms), (mp_obj_t)&time_sleep_ms_obj },
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{ MP_OBJ_NEW_QSTR(MP_QSTR_sleep_us), (mp_obj_t)&time_sleep_us_obj },
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{ MP_OBJ_NEW_QSTR(MP_QSTR_ticks_ms), (mp_obj_t)&time_ticks_ms_obj },
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};
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STATIC MP_DEFINE_CONST_DICT(time_module_globals, time_module_globals_table);

‎atmel-samd/mphalport.c‎

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Original file line numberDiff line numberDiff line change
@@ -210,3 +210,35 @@ void mp_hal_delay_us(mp_uint_t delay) {
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}
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delay_us(delay);
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}
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// Global millisecond tick count (driven by SysTick interrupt handler).
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volatile uint32_t systick_ticks_ms = 0;
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void SysTick_Handler(void) {
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// SysTick interrupt handler called when the SysTick timer reaches zero
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// (every millisecond).
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systick_ticks_ms += 1;
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// Keep the counter within the range of 31 bit uint values since that's the
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// max value for micropython 'small' ints.
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systick_ticks_ms = systick_ticks_ms > 2147483647L ? 0 : systick_ticks_ms;
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}
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// Interrupt flags that will be saved and restored during disable/Enable
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// interrupt functions below.
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static irqflags_t irq_flags;
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void mp_hal_disable_all_interrupts(void) {
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// Disable all interrupt sources for timing critical sections.
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// Disable ASF-based interrupts.
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irq_flags = cpu_irq_save();
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// Disable SysTick interrupt.
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SysTick->CTRL &= ~SysTick_CTRL_TICKINT_Msk;
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}
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void mp_hal_enable_all_interrupts(void) {
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// Enable all interrupt sources after timing critical sections.
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// Restore ASF-based interrupts.
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cpu_irq_restore(irq_flags);
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// Restore SysTick interrupt.
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SysTick->CTRL |= SysTick_CTRL_TICKINT_Msk;
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}

‎atmel-samd/mphalport.h‎

Lines changed: 13 additions & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -27,9 +27,21 @@
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#ifndef __MICROPY_INCLUDED_ATMEL_SAMD_MPHALPORT_H__
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#define __MICROPY_INCLUDED_ATMEL_SAMD_MPHALPORT_H__
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#include "py/obj.h"
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#define USB_RX_BUF_SIZE 128
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static inline mp_uint_t mp_hal_ticks_ms(void) { return 0; }
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// Global millisecond tick count (driven by SysTick interrupt).
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extern volatile uint32_t systick_ticks_ms;
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static inline mp_uint_t mp_hal_ticks_ms(void) {
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return systick_ticks_ms;
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}
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void mp_hal_set_interrupt_char(int c);
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void mp_hal_disable_all_interrupts(void);
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void mp_hal_enable_all_interrupts(void);
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#endif // __MICROPY_INCLUDED_ATMEL_SAMD_MPHALPORT_H__

‎atmel-samd/samdneopixel.c‎

Lines changed: 4 additions & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -1,6 +1,8 @@
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#include "asf/common2/services/delay/delay.h"
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#include "asf/sam0/drivers/port/port.h"
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#include "mphalport.h"
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#include "samdneopixel.h"
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void samd_neopixel_write(uint32_t pin, uint8_t *pixels, uint32_t numBytes, bool is800KHz) {
@@ -11,7 +13,7 @@ void samd_neopixel_write(uint32_t pin, uint8_t *pixels, uint32_t numBytes, bool
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PortGroup* port;
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// Turn off interrupts of any kind during timing-sensitive code.
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irqflags_t flags = cpu_irq_save();
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mp_hal_disable_all_interrupts();
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port = port_get_group_from_gpio_pin(pin);
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pinMask = (1UL << (pin % 32)); // From port_pin_set_output_level ASF code.
@@ -78,7 +80,7 @@ void samd_neopixel_write(uint32_t pin, uint8_t *pixels, uint32_t numBytes, bool
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}
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// Turn on interrupts after timing-sensitive code.
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cpu_irq_restore(flags);
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mp_hal_enable_all_interrupts();
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// 50ms delay to let pixels latch to the data that was just sent.
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// This could be optimized to only occur before pixel writes when necessary,

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