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circuitpython/shared-bindings/i2cslave/__init__.c

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/*
* This file is part of the MicroPython project, http://micropython.org/
*
* The MIT License (MIT)
*
* Copyright (c) 2018 Noralf Trønnes
*
* 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 <stdint.h>
#include "py/obj.h"
#include "py/runtime.h"
#include "shared-bindings/microcontroller/Pin.h"
//#include "shared-bindings/i2cslave/__init__.h"
#include "shared-bindings/i2cslave/I2CSlave.h"
#include "py/runtime.h"
//| :mod:`i2cslave` --- Two wire serial protocol slave
//| ==================================================
//|
//| .. module:: i2cslave
//| :synopsis: Two wire serial protocol slave
//| :platform: SAMD21, SAMD51
//|
//| The `i2cslave` module contains classes to support a I2C slave.
//|
//| Classes
//|
//| .. toctree::
//| :maxdepth: 3
//|
//| I2CSlave
//|
//| Example emulating 2 devices::
//|
//| import board
//| from i2cslave import I2CSlave
//|
//| regs = [0] * 16
//| index = 0
//|
//| with I2CSlave(board.SCL, board.SDA, (0x40, 0x41)) as slave:
//| while True:
//| r = slave.request()
//| if not r:
//| # Maybe do some housekeeping
//| continue
//| with r: # Closes the transfer if necessary by sending a NACK or feeding the master dummy bytes
//| if r.address == 0x40:
//| if not r.is_read: # Master write which is Slave read
//| b = r.read(1)
//| if not b or b[0] > 15:
//| break
//| index = b[0]
//| b = r.read(1)
//| if b:
//| regs[index] = b[0]
//| elif r.is_restart: # Combined transfer: This is the Master read message
//| n = r.write(bytes([regs[index]]))
//| #else:
//| # A read transfer is not supported in this example
//| # If the Master tries, it will get 0xff byte(s) by the ctx manager (r.close())
//| elif r.address == 0x41:
//| if not r.is_read:
//| b = r.read(1)
//| if b and b[0] == 0xde:
//| # do something
//| pass
//|
//| This example sets up an I2C slave that can be accessed from Linux like this::
//|
//| $ i2cget -y 1 0x40 0x01
//| 0x00
//| $ i2cset -y 1 0x40 0x01 0xaa
//| $ i2cget -y 1 0x40 0x01
//| 0xaa
//|
//| .. warning::
//| I2CSlave makes use of clock stretching in order to slow down the master.
//| Make sure the I2C master supports this.
//|
//| Raspberry Pi in particular does not support this with its I2C hw block.
//| This can be worked around by using the ``i2c-gpio`` bit banging driver.
//| Since the RPi firmware uses the hw i2c, it's not possible to emulate a HAT eeprom.
//|
STATIC const mp_rom_map_elem_t i2cslave_module_globals_table[] = {
{ MP_ROM_QSTR(MP_QSTR___name__), MP_ROM_QSTR(MP_QSTR_i2cslave) },
{ MP_ROM_QSTR(MP_QSTR_I2CSlave), MP_ROM_PTR(&i2cslave_i2c_slave_type) },
};
STATIC MP_DEFINE_CONST_DICT(i2cslave_module_globals, i2cslave_module_globals_table);
const mp_obj_module_t i2cslave_module = {
.base = { &mp_type_module },
.globals = (mp_obj_dict_t*)&i2cslave_module_globals,
};