103 lines
3.9 KiB
Plaintext
103 lines
3.9 KiB
Plaintext
/*
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ChibiOS/RT - Copyright (C) 2006,2007,2008,2009,2010,
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2011,2012,2013 Giovanni Di Sirio.
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This file is part of ChibiOS/RT.
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ChibiOS/RT is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 3 of the License, or
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(at your option) any later version.
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ChibiOS/RT is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program. If not, see <http://www.gnu.org/licenses/>.
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*/
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/**
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* @defgroup I2C I2C Driver
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* @brief Generic I2C Driver.
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* @details This module implements a generic I2C (Inter-Integrated Circuit)
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* driver.
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* @pre In order to use the I2C driver the @p HAL_USE_I2C option
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* must be enabled in @p halconf.h.
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*
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* @section i2c_1 Driver State Machine
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* The driver implements a state machine internally, not all the driver
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* functionalities can be used in any moment, any transition not explicitly
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* shown in the following diagram has to be considered an error and shall
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* be captured by an assertion (if enabled).
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* @if LATEX_PDF
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* @dot
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digraph example {
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size="5, 7";
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rankdir="LR";
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node [shape=circle, fontname=Helvetica, fontsize=8, fixedsize="true",
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width="0.9", height="0.9"];
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edge [fontname=Helvetica, fontsize=8];
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stop [label="I2C_STOP\nLow Power"];
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uninit [label="I2C_UNINIT", style="bold"];
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ready [label="I2C_READY\nClock Enabled"];
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active_tx [label="I2C_ACTIVE_TX\nBus TX Active"];
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active_rx [label="I2C_ACTIVE_RX\nBus RX Active"];
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locked [label="I2C_LOCKED\nBus Locked"];
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uninit -> stop [label="i2cInit()", constraint=false];
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stop -> stop [label="i2cStop()"];
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stop -> ready [label="i2cStart()"];
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ready -> ready [label="i2cStart()"];
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ready -> stop [label="i2cStop()"];
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ready -> active_tx [label="i2cMasterTransmit()"];
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ready -> active_rx [label="i2cMasterReceive()"];
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active_tx -> ready [label="completed"];
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active_rx -> ready [label="completed"];
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active_tx -> locked [label="RDY_TIMEOUT"];
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active_rx -> locked [label="RDY_TIMEOUT"];
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locked -> stop [label="i2cStop()"];
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locked -> ready [label="i2cStart()"];
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}
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* @else
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* @dot
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digraph example {
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rankdir="LR";
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node [shape=circle, fontname=Helvetica, fontsize=8, fixedsize="true",
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width="0.9", height="0.9"];
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edge [fontname=Helvetica, fontsize=8];
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stop [label="I2C_STOP\nLow Power"];
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uninit [label="I2C_UNINIT", style="bold"];
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ready [label="I2C_READY\nClock Enabled"];
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active_tx [label="I2C_ACTIVE_TX\nBus TX Active"];
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active_rx [label="I2C_ACTIVE_RX\nBus RX Active"];
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locked [label="I2C_LOCKED\nBus Locked"];
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uninit -> stop [label="i2cInit()", constraint=false];
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stop -> stop [label="i2cStop()"];
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stop -> ready [label="i2cStart()"];
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ready -> ready [label="i2cStart()"];
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ready -> stop [label="i2cStop()"];
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ready -> active_tx [label="i2cMasterTransmit()"];
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ready -> active_rx [label="i2cMasterReceive()"];
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active_tx -> ready [label="completed"];
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active_rx -> ready [label="completed"];
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active_tx -> locked [label="RDY_TIMEOUT"];
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active_rx -> locked [label="RDY_TIMEOUT"];
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locked -> stop [label="i2cStop()"];
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locked -> ready [label="i2cStart()"];
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}
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* @enddot
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* @endif
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* The driver is not thread safe for performance reasons, if you need to access
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* the I2C bus from multiple threads then use the @p i2cAcquireBus() and
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* @p i2cReleaseBus() APIs in order to gain exclusive access.
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*
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* @ingroup IO
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*/
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