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