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dpgeorgepfalcon
dpgeorge
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esp8266: Implement software SPI class.
Supports speeds up to 500k baud, polarity=0/1, phase=0/1, and using any pins. Only supports MSB output at the moment.
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‎esp8266/Makefile‎

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@@ -62,6 +62,7 @@ SRC_C = \
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modpybrtc.c \
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modpybadc.c \
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modpybi2c.c \
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modpybspi.c \
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modesp.c \
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modnetwork.c \
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modutime.c \

‎esp8266/esp8266.ld‎

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@@ -133,6 +133,7 @@ SECTIONS
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*modpybpin.o(.literal*, .text*)
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*modpybrtc.o(.literal*, .text*)
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*modpybadc.o(.literal*, .text*)
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*modpybspi.o(.literal*, .text*)
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*modesp.o(.literal* .text*)
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*modnetwork.o(.literal* .text*)
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*moduos.o(.literal* .text*)

‎esp8266/modmachine.c‎

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@@ -143,6 +143,7 @@ STATIC const mp_rom_map_elem_t machine_module_globals_table[] = {
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{ MP_ROM_QSTR(MP_QSTR_Timer), MP_ROM_PTR(&esp_timer_type) },
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{ MP_ROM_QSTR(MP_QSTR_Pin), MP_ROM_PTR(&pyb_pin_type) },
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{ MP_ROM_QSTR(MP_QSTR_I2C), MP_ROM_PTR(&pyb_i2c_type) },
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{ MP_ROM_QSTR(MP_QSTR_SPI), MP_ROM_PTR(&pyb_spi_type) },
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};
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STATIC MP_DEFINE_CONST_DICT(machine_module_globals, machine_module_globals_table);

‎esp8266/modpyb.h‎

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@@ -2,6 +2,7 @@ extern const mp_obj_type_t pyb_pin_type;
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extern const mp_obj_type_t pyb_adc_type;
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extern const mp_obj_type_t pyb_rtc_type;
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extern const mp_obj_type_t pyb_i2c_type;
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extern const mp_obj_type_t pyb_spi_type;
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typedef struct _pyb_pin_obj_t {
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mp_obj_base_t base;

‎esp8266/modpybspi.c‎

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/*
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* This file is part of the MicroPython project, http://micropython.org/
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*
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* The MIT License (MIT)
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*
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* Copyright (c) 2016 Damien P. George
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*
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* Permission is hereby granted, free of charge, to any person obtaining a copy
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* of this software and associated documentation files (the "Software"), to deal
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* in the Software without restriction, including without limitation the rights
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* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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* copies of the Software, and to permit persons to whom the Software is
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* furnished to do so, subject to the following conditions:
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*
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* The above copyright notice and this permission notice shall be included in
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* all copies or substantial portions of the Software.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
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* THE SOFTWARE.
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*/
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#include <stdio.h>
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#include <stdint.h>
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#include <string.h>
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#include <errno.h>
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#include "ets_sys.h"
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#include "etshal.h"
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#include "ets_alt_task.h"
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#include "py/runtime.h"
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#include "py/stream.h"
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#include "modpyb.h"
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typedef struct _pyb_spi_obj_t {
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mp_obj_base_t base;
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uint32_t baudrate;
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uint8_t polarity;
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uint8_t phase;
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pyb_pin_obj_t *sck;
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pyb_pin_obj_t *mosi;
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pyb_pin_obj_t *miso;
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} pyb_spi_obj_t;
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STATIC void mp_hal_spi_transfer(pyb_spi_obj_t *self, size_t src_len, const uint8_t *src_buf, size_t dest_len, uint8_t *dest_buf) {
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// only MSB transfer is implemented
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uint32_t delay_half = 500000 / self->baudrate + 1;
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for (size_t i = 0; i < src_len || i < dest_len; ++i) {
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uint8_t data_out;
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if (src_len == 1) {
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data_out = src_buf[0];
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} else {
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data_out = src_buf[i];
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}
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uint8_t data_in = 0;
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for (int j = 0; j < 8; ++j, data_out <<= 1) {
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pin_set(self->mosi->phys_port, (data_out >> 7) & 1);
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if (self->phase == 0) {
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ets_delay_us(delay_half);
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pin_set(self->sck->phys_port, 1 - self->polarity);
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} else {
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pin_set(self->sck->phys_port, 1 - self->polarity);
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ets_delay_us(delay_half);
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}
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data_in = (data_in << 1) | pin_get(self->miso->phys_port);
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if (self->phase == 0) {
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ets_delay_us(delay_half);
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pin_set(self->sck->phys_port, self->polarity);
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} else {
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pin_set(self->sck->phys_port, self->polarity);
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ets_delay_us(delay_half);
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}
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}
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if (dest_len != 0) {
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dest_buf[i] = data_in;
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}
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// make sure pending tasks have a chance to run
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ets_loop_iter();
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}
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}
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/******************************************************************************/
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// MicroPython bindings for SPI
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STATIC void pyb_spi_print(const mp_print_t *print, mp_obj_t self_in, mp_print_kind_t kind) {
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pyb_spi_obj_t *self = MP_OBJ_TO_PTR(self_in);
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mp_printf(print, "SPI(baudrate=%u, polarity=%u, phase=%u, sck=%u, mosi=%u, miso=%u)",
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self->baudrate, self->polarity, self->phase, self->sck->phys_port, self->mosi->phys_port, self->miso->phys_port);
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}
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STATIC void pyb_spi_init_helper(pyb_spi_obj_t *self, size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) {
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enum { ARG_baudrate, ARG_polarity, ARG_phase, ARG_sck, ARG_mosi, ARG_miso };
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static const mp_arg_t allowed_args[] = {
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{ MP_QSTR_baudrate, MP_ARG_INT, {.u_int = -1} },
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{ MP_QSTR_polarity, MP_ARG_INT, {.u_int = -1} },
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{ MP_QSTR_phase, MP_ARG_INT, {.u_int = -1} },
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{ MP_QSTR_sck, MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
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{ MP_QSTR_mosi, MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
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{ MP_QSTR_miso, MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
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};
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mp_arg_val_t args[MP_ARRAY_SIZE(allowed_args)];
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mp_arg_parse_all(n_args, pos_args, kw_args, MP_ARRAY_SIZE(allowed_args), allowed_args, args);
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if (args[ARG_baudrate].u_int != -1) {
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self->baudrate = args[ARG_baudrate].u_int;
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}
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if (args[ARG_polarity].u_int != -1) {
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self->polarity = args[ARG_polarity].u_int;
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}
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if (args[ARG_phase].u_int != -1) {
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self->phase = args[ARG_phase].u_int;
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}
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if (args[ARG_sck].u_obj != MP_OBJ_NULL) {
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self->sck = mp_obj_get_pin_obj(args[ARG_sck].u_obj);
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}
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if (args[ARG_mosi].u_obj != MP_OBJ_NULL) {
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self->mosi = mp_obj_get_pin_obj(args[ARG_mosi].u_obj);
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}
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if (args[ARG_miso].u_obj != MP_OBJ_NULL) {
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self->miso = mp_obj_get_pin_obj(args[ARG_miso].u_obj);
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}
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}
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STATIC mp_obj_t pyb_spi_make_new(const mp_obj_type_t *type, size_t n_args, size_t n_kw, const mp_obj_t *args) {
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mp_arg_check_num(n_args, n_kw, 0, MP_OBJ_FUN_ARGS_MAX, true);
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pyb_spi_obj_t *self = m_new_obj(pyb_spi_obj_t);
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self->base.type = &pyb_spi_type;
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// set defaults
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self->baudrate = 500000;
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self->polarity = 0;
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self->phase = 0;
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self->sck = NULL;
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self->mosi = NULL;
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self->miso = NULL;
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mp_map_t kw_args;
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mp_map_init_fixed_table(&kw_args, n_kw, args + n_args);
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pyb_spi_init_helper(self, n_args, args, &kw_args);
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return MP_OBJ_FROM_PTR(self);
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}
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STATIC mp_obj_t pyb_spi_init(size_t n_args, const mp_obj_t *args, mp_map_t *kw_args) {
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pyb_spi_init_helper(args[0], n_args - 1, args + 1, kw_args);
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return mp_const_none;
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}
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MP_DEFINE_CONST_FUN_OBJ_KW(pyb_spi_init_obj, 1, pyb_spi_init);
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STATIC mp_obj_t pyb_spi_read(size_t n_args, const mp_obj_t *args) {
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pyb_spi_obj_t *self = MP_OBJ_TO_PTR(args[0]);
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uint8_t write_byte = 0;
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if (n_args == 3) {
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write_byte = mp_obj_get_int(args[2]);
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}
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vstr_t vstr;
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vstr_init_len(&vstr, mp_obj_get_int(args[1]));
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mp_hal_spi_transfer(self, 1, &write_byte, vstr.len, (uint8_t*)vstr.buf);
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return mp_obj_new_str_from_vstr(&mp_type_bytes, &vstr);
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}
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MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(pyb_spi_read_obj, 2, 3, pyb_spi_read);
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STATIC mp_obj_t pyb_spi_readinto(size_t n_args, const mp_obj_t *args) {
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pyb_spi_obj_t *self = MP_OBJ_TO_PTR(args[0]);
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mp_buffer_info_t bufinfo;
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mp_get_buffer_raise(args[1], &bufinfo, MP_BUFFER_WRITE);
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uint8_t write_byte = 0;
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if (n_args == 3) {
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write_byte = mp_obj_get_int(args[2]);
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}
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mp_hal_spi_transfer(self, 1, &write_byte, bufinfo.len, (uint8_t*)bufinfo.buf);
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return mp_const_none;
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}
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MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(pyb_spi_readinto_obj, 2, 3, pyb_spi_readinto);
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STATIC mp_obj_t pyb_spi_write(mp_obj_t self_in, mp_obj_t wr_buf_in) {
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pyb_spi_obj_t *self = MP_OBJ_TO_PTR(self_in);
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mp_buffer_info_t src_buf;
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mp_get_buffer_raise(wr_buf_in, &src_buf, MP_BUFFER_READ);
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mp_hal_spi_transfer(self, src_buf.len, (const uint8_t*)src_buf.buf, 0, NULL);
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return mp_const_none;
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}
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MP_DEFINE_CONST_FUN_OBJ_2(pyb_spi_write_obj, pyb_spi_write);
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STATIC mp_obj_t pyb_spi_write_readinto(mp_obj_t self_in, mp_obj_t wr_buf_in, mp_obj_t rd_buf_in) {
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pyb_spi_obj_t *self = MP_OBJ_TO_PTR(self_in);
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mp_buffer_info_t src_buf;
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mp_get_buffer_raise(wr_buf_in, &src_buf, MP_BUFFER_READ);
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mp_buffer_info_t dest_buf;
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mp_get_buffer_raise(rd_buf_in, &dest_buf, MP_BUFFER_WRITE);
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if (src_buf.len != dest_buf.len) {
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nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_ValueError, "buffers must be the same length"));
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}
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mp_hal_spi_transfer(self, src_buf.len, (const uint8_t*)src_buf.buf, dest_buf.len, (uint8_t*)dest_buf.buf);
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return mp_const_none;
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}
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MP_DEFINE_CONST_FUN_OBJ_3(pyb_spi_write_readinto_obj, pyb_spi_write_readinto);
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STATIC const mp_rom_map_elem_t pyb_spi_locals_dict_table[] = {
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{ MP_ROM_QSTR(MP_QSTR_init), MP_ROM_PTR(&pyb_spi_init_obj) },
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{ MP_ROM_QSTR(MP_QSTR_read), MP_ROM_PTR(&pyb_spi_read_obj) },
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{ MP_ROM_QSTR(MP_QSTR_readinto), MP_ROM_PTR(&pyb_spi_readinto_obj) },
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{ MP_ROM_QSTR(MP_QSTR_write), MP_ROM_PTR(&pyb_spi_write_obj) },
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{ MP_ROM_QSTR(MP_QSTR_write_readinto), MP_ROM_PTR(&pyb_spi_write_readinto_obj) },
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};
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STATIC MP_DEFINE_CONST_DICT(pyb_spi_locals_dict, pyb_spi_locals_dict_table);
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const mp_obj_type_t pyb_spi_type = {
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{ &mp_type_type },
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.name = MP_QSTR_SPI,
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.print = pyb_spi_print,
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.make_new = pyb_spi_make_new,
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.locals_dict = (mp_obj_dict_t*)&pyb_spi_locals_dict,
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};

‎esp8266/qstrdefsport.h‎

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@@ -155,6 +155,20 @@ Q(buf)
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Q(addr)
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Q(n)
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// SPI
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Q(SPI)
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Q(init)
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Q(baudrate)
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Q(phase)
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Q(polarity)
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Q(sck)
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Q(mosi)
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Q(miso)
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Q(read)
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Q(readinto)
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Q(write)
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Q(write_readinto)
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// utime
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Q(utime)
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Q(localtime)

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