From 78d0dde5622aa9ab55b7dfc0dc26407734580780 Mon Sep 17 00:00:00 2001 From: Damien George Date: Tue, 29 Dec 2015 00:20:34 +0000 Subject: [PATCH] esp8266: Add onewire helper functions as C module. Includes functions to read and write bits and bytes. --- esp8266/Makefile | 1 + esp8266/modonewire.c | 185 +++++++++++++++++++++++++++++++++++++++++ esp8266/mpconfigport.h | 2 + esp8266/qstrdefsport.h | 11 +++ 4 files changed, 199 insertions(+) create mode 100644 esp8266/modonewire.c diff --git a/esp8266/Makefile b/esp8266/Makefile index c742ceffa6..9bf6bc2c23 100644 --- a/esp8266/Makefile +++ b/esp8266/Makefile @@ -67,6 +67,7 @@ SRC_C = \ modutime.c \ moduos.c \ modmachine.c \ + modonewire.c \ utils.c \ ets_alt_task.c \ $(BUILD)/frozen.c \ diff --git a/esp8266/modonewire.c b/esp8266/modonewire.c new file mode 100644 index 0000000000..267da281ed --- /dev/null +++ b/esp8266/modonewire.c @@ -0,0 +1,185 @@ +/* + * This file is part of the MicroPython project, http://micropython.org/ + * + * The MIT License (MIT) + * + * Copyright (c) 2015 Damien P. George + * + * 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 +#include + +#include "etshal.h" +#include "user_interface.h" +#include "py/obj.h" +#include "py/mphal.h" +#include "modpyb.h" + +STATIC uint32_t disable_irq(void) { + ets_intr_lock(); + return 0; +} + +STATIC void enable_irq(uint32_t i) { + ets_intr_unlock(); +} + +STATIC void mp_hal_delay_us_no_irq(uint32_t us) { + uint32_t start = system_get_time(); + while (system_get_time() - start < us) { + } +} + +#define DELAY_US mp_hal_delay_us_no_irq + +#define TIMING_RESET1 (0) +#define TIMING_RESET2 (1) +#define TIMING_RESET3 (2) +#define TIMING_READ1 (3) +#define TIMING_READ2 (4) +#define TIMING_READ3 (5) +#define TIMING_WRITE1 (6) +#define TIMING_WRITE2 (7) +#define TIMING_WRITE3 (8) + +static int timings[] = {480, 40, 420, 5, 5, 40, 10, 50, 10}; + +STATIC mp_obj_t onewire_timings(mp_obj_t timings_in) { + mp_obj_t *items; + mp_obj_get_array_fixed_n(timings_in, 9, &items); + for (int i = 0; i < 9; ++i) { + timings[i] = mp_obj_get_int(items[i]); + } + return mp_const_none; +} +STATIC MP_DEFINE_CONST_FUN_OBJ_1(onewire_timings_obj, onewire_timings); + +STATIC mp_obj_t onewire_reset(mp_obj_t pin_in) { + uint pin = mp_obj_get_pin(pin_in); + pin_set(pin, 0); + DELAY_US(timings[TIMING_RESET1]); + uint32_t i = disable_irq(); + pin_set(pin, 1); + DELAY_US(timings[TIMING_RESET2]); + int status = !pin_get(pin); + enable_irq(i); + DELAY_US(timings[TIMING_RESET3]); + return mp_obj_new_bool(status); +} +STATIC MP_DEFINE_CONST_FUN_OBJ_1(onewire_reset_obj, onewire_reset); + +STATIC int _onewire_readbit(uint pin) { + pin_set(pin, 1); + uint32_t i = disable_irq(); + pin_set(pin, 0); + DELAY_US(timings[TIMING_READ1]); + pin_set(pin, 1); + DELAY_US(timings[TIMING_READ2]); + int value = pin_get(pin); + enable_irq(i); + DELAY_US(timings[TIMING_READ3]); + return value; +} + +STATIC mp_obj_t onewire_readbit(mp_obj_t pin_in) { + return MP_OBJ_NEW_SMALL_INT(_onewire_readbit(mp_obj_get_pin(pin_in))); +} +STATIC MP_DEFINE_CONST_FUN_OBJ_1(onewire_readbit_obj, onewire_readbit); + +STATIC mp_obj_t onewire_readbyte(mp_obj_t pin_in) { + uint pin = mp_obj_get_pin(pin_in); + uint8_t value = 0; + for (int i = 0; i < 8; ++i) { + value |= _onewire_readbit(pin) << i; + } + return MP_OBJ_NEW_SMALL_INT(value); +} +STATIC MP_DEFINE_CONST_FUN_OBJ_1(onewire_readbyte_obj, onewire_readbyte); + +STATIC void _onewire_writebit(uint pin, int value) { + uint32_t i = disable_irq(); + pin_set(pin, 0); + DELAY_US(timings[TIMING_WRITE1]); + pin_set(pin, value); + DELAY_US(timings[TIMING_WRITE2]); + pin_set(pin, 1); + DELAY_US(timings[TIMING_WRITE3]); + enable_irq(i); +} + +STATIC mp_obj_t onewire_writebit(mp_obj_t pin_in, mp_obj_t value_in) { + _onewire_writebit(mp_obj_get_pin(pin_in), mp_obj_get_int(value_in)); + return mp_const_none; +} +STATIC MP_DEFINE_CONST_FUN_OBJ_2(onewire_writebit_obj, onewire_writebit); + +STATIC mp_obj_t onewire_writebyte(mp_obj_t pin_in, mp_obj_t value_in) { + uint pin = mp_obj_get_pin(pin_in); + int value = mp_obj_get_int(value_in); + for (int i = 0; i < 8; ++i) { + _onewire_writebit(pin, value & 1); + value >>= 1; + } + return mp_const_none; +} +STATIC MP_DEFINE_CONST_FUN_OBJ_2(onewire_writebyte_obj, onewire_writebyte); + +STATIC mp_obj_t onewire_crc8(mp_obj_t data) { + mp_buffer_info_t bufinfo; + mp_get_buffer_raise(data, &bufinfo, MP_BUFFER_READ); + uint8_t crc = 0; + for (size_t i = 0; i < bufinfo.len; ++i) { + uint8_t byte = ((uint8_t*)bufinfo.buf)[i]; + for (int b = 0; b < 8; ++b) { + uint8_t fb_bit = (crc ^ byte) & 0x01; + if (fb_bit == 0x01) { + crc = crc ^ 0x18; + } + crc = (crc >> 1) & 0x7f; + if (fb_bit == 0x01) { + crc = crc | 0x80; + } + byte = byte >> 1; + } + } + return MP_OBJ_NEW_SMALL_INT(crc); +} +STATIC MP_DEFINE_CONST_FUN_OBJ_1(onewire_crc8_obj, onewire_crc8); + +STATIC const mp_map_elem_t onewire_module_globals_table[] = { + { MP_ROM_QSTR(MP_QSTR___name__), MP_ROM_QSTR(MP_QSTR_onewire) }, + + { MP_ROM_QSTR(MP_QSTR_timings), MP_ROM_PTR((mp_obj_t)&onewire_timings_obj) }, + { MP_ROM_QSTR(MP_QSTR_reset), MP_ROM_PTR((mp_obj_t)&onewire_reset_obj) }, + { MP_ROM_QSTR(MP_QSTR_readbit), MP_ROM_PTR((mp_obj_t)&onewire_readbit_obj) }, + { MP_ROM_QSTR(MP_QSTR_readbyte), MP_ROM_PTR((mp_obj_t)&onewire_readbyte_obj) }, + { MP_ROM_QSTR(MP_QSTR_writebit), MP_ROM_PTR((mp_obj_t)&onewire_writebit_obj) }, + { MP_ROM_QSTR(MP_QSTR_writebyte), MP_ROM_PTR((mp_obj_t)&onewire_writebyte_obj) }, + { MP_ROM_QSTR(MP_QSTR_crc8), MP_ROM_PTR((mp_obj_t)&onewire_crc8_obj) }, +}; + +STATIC MP_DEFINE_CONST_DICT(onewire_module_globals, onewire_module_globals_table); + +const mp_obj_module_t onewire_module = { + .base = { &mp_type_module }, + .name = MP_QSTR_onewire, + .globals = (mp_obj_dict_t*)&onewire_module_globals, +}; diff --git a/esp8266/mpconfigport.h b/esp8266/mpconfigport.h index cedc6dd405..aee1220f66 100644 --- a/esp8266/mpconfigport.h +++ b/esp8266/mpconfigport.h @@ -94,6 +94,7 @@ extern const struct _mp_obj_module_t utime_module; extern const struct _mp_obj_module_t uos_module; extern const struct _mp_obj_module_t mp_module_lwip; extern const struct _mp_obj_module_t mp_module_machine; +extern const struct _mp_obj_module_t onewire_module; #define MICROPY_PORT_BUILTIN_MODULES \ { MP_OBJ_NEW_QSTR(MP_QSTR_pyb), (mp_obj_t)&pyb_module }, \ @@ -105,6 +106,7 @@ extern const struct _mp_obj_module_t mp_module_machine; { MP_OBJ_NEW_QSTR(MP_QSTR_utime), (mp_obj_t)&utime_module }, \ { MP_OBJ_NEW_QSTR(MP_QSTR_uos), (mp_obj_t)&uos_module }, \ { MP_OBJ_NEW_QSTR(MP_QSTR_machine), (mp_obj_t)&mp_module_machine }, \ + { MP_OBJ_NEW_QSTR(MP_QSTR__onewire), (mp_obj_t)&onewire_module }, \ #define MICROPY_PORT_BUILTIN_MODULE_WEAK_LINKS \ { MP_OBJ_NEW_QSTR(MP_QSTR_time), (mp_obj_t)&utime_module }, \ diff --git a/esp8266/qstrdefsport.h b/esp8266/qstrdefsport.h index 5687538928..6f43784201 100644 --- a/esp8266/qstrdefsport.h +++ b/esp8266/qstrdefsport.h @@ -178,4 +178,15 @@ Q(period) Q(ONE_SHOT) Q(PERIODIC) +// onewire +Q(_onewire) +Q(onewire) +Q(timings) +Q(reset) +Q(readbit) +Q(readbyte) +Q(writebit) +Q(writebyte) +Q(crc8) + Q(json)