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DevI2C.h@2:40f590e28101, 2017-03-31 (annotated)
- Committer:
- mwilkens241
- Date:
- Fri Mar 31 15:49:47 2017 +0000
- Revision:
- 2:40f590e28101
- Parent:
- 0:15e49005d54e
stole some things out of here, not much changed
Who changed what in which revision?
| User | Revision | Line number | New contents of line |
|---|---|---|---|
| mwilkens241 | 0:15e49005d54e | 1 | /** |
| mwilkens241 | 0:15e49005d54e | 2 | ****************************************************************************** |
| mwilkens241 | 0:15e49005d54e | 3 | * @file DevI2C.h |
| mwilkens241 | 0:15e49005d54e | 4 | * @author AST / EST |
| mwilkens241 | 0:15e49005d54e | 5 | * @version V1.1.0 |
| mwilkens241 | 0:15e49005d54e | 6 | * @date 21-January-2016 |
| mwilkens241 | 0:15e49005d54e | 7 | * @brief Header file for a special I2C class DevI2C which provides some |
| mwilkens241 | 0:15e49005d54e | 8 | * helper function for on-board communication |
| mwilkens241 | 0:15e49005d54e | 9 | ****************************************************************************** |
| mwilkens241 | 0:15e49005d54e | 10 | * @attention |
| mwilkens241 | 0:15e49005d54e | 11 | * |
| mwilkens241 | 0:15e49005d54e | 12 | * <h2><center>© COPYRIGHT(c) 2016 STMicroelectronics</center></h2> |
| mwilkens241 | 0:15e49005d54e | 13 | * |
| mwilkens241 | 0:15e49005d54e | 14 | * Redistribution and use in source and binary forms, with or without modification, |
| mwilkens241 | 0:15e49005d54e | 15 | * are permitted provided that the following conditions are met: |
| mwilkens241 | 0:15e49005d54e | 16 | * 1. Redistributions of source code must retain the above copyright notice, |
| mwilkens241 | 0:15e49005d54e | 17 | * this list of conditions and the following disclaimer. |
| mwilkens241 | 0:15e49005d54e | 18 | * 2. Redistributions in binary form must reproduce the above copyright notice, |
| mwilkens241 | 0:15e49005d54e | 19 | * this list of conditions and the following disclaimer in the documentation |
| mwilkens241 | 0:15e49005d54e | 20 | * and/or other materials provided with the distribution. |
| mwilkens241 | 0:15e49005d54e | 21 | * 3. Neither the name of STMicroelectronics nor the names of its contributors |
| mwilkens241 | 0:15e49005d54e | 22 | * may be used to endorse or promote products derived from this software |
| mwilkens241 | 0:15e49005d54e | 23 | * without specific prior written permission. |
| mwilkens241 | 0:15e49005d54e | 24 | * |
| mwilkens241 | 0:15e49005d54e | 25 | * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" |
| mwilkens241 | 0:15e49005d54e | 26 | * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| mwilkens241 | 0:15e49005d54e | 27 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE |
| mwilkens241 | 0:15e49005d54e | 28 | * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE |
| mwilkens241 | 0:15e49005d54e | 29 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| mwilkens241 | 0:15e49005d54e | 30 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR |
| mwilkens241 | 0:15e49005d54e | 31 | * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER |
| mwilkens241 | 0:15e49005d54e | 32 | * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, |
| mwilkens241 | 0:15e49005d54e | 33 | * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| mwilkens241 | 0:15e49005d54e | 34 | * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| mwilkens241 | 0:15e49005d54e | 35 | * |
| mwilkens241 | 0:15e49005d54e | 36 | ****************************************************************************** |
| mwilkens241 | 0:15e49005d54e | 37 | */ |
| mwilkens241 | 0:15e49005d54e | 38 | |
| mwilkens241 | 0:15e49005d54e | 39 | /* Define to prevent from recursive inclusion --------------------------------*/ |
| mwilkens241 | 0:15e49005d54e | 40 | #ifndef __DEV_I2C_H |
| mwilkens241 | 0:15e49005d54e | 41 | #define __DEV_I2C_H |
| mwilkens241 | 0:15e49005d54e | 42 | |
| mwilkens241 | 0:15e49005d54e | 43 | /* Includes ------------------------------------------------------------------*/ |
| mwilkens241 | 0:15e49005d54e | 44 | #include "mbed.h" |
| mwilkens241 | 0:15e49005d54e | 45 | #include "pinmap.h" |
| mwilkens241 | 0:15e49005d54e | 46 | |
| mwilkens241 | 0:15e49005d54e | 47 | /* Classes -------------------------------------------------------------------*/ |
| mwilkens241 | 0:15e49005d54e | 48 | /** Helper class DevI2C providing functions for multi-register I2C communication |
| mwilkens241 | 0:15e49005d54e | 49 | * common for a series of I2C devices |
| mwilkens241 | 0:15e49005d54e | 50 | */ |
| mwilkens241 | 0:15e49005d54e | 51 | class DevI2C : public I2C |
| mwilkens241 | 0:15e49005d54e | 52 | { |
| mwilkens241 | 0:15e49005d54e | 53 | public: |
| mwilkens241 | 0:15e49005d54e | 54 | /** Create a DevI2C Master interface, connected to the specified pins |
| mwilkens241 | 0:15e49005d54e | 55 | * |
| mwilkens241 | 0:15e49005d54e | 56 | * @param sda I2C data line pin |
| mwilkens241 | 0:15e49005d54e | 57 | * @param scl I2C clock line pin |
| mwilkens241 | 0:15e49005d54e | 58 | */ |
| mwilkens241 | 0:15e49005d54e | 59 | DevI2C(PinName sda, PinName scl) : I2C(sda, scl) {} |
| mwilkens241 | 0:15e49005d54e | 60 | |
| mwilkens241 | 0:15e49005d54e | 61 | /** Create a DevI2C Master interface, connected to the specified pins and set their pin modes |
| mwilkens241 | 0:15e49005d54e | 62 | * |
| mwilkens241 | 0:15e49005d54e | 63 | * @param sda I2C data line pin |
| mwilkens241 | 0:15e49005d54e | 64 | * @param sda I2C data pin mode |
| mwilkens241 | 0:15e49005d54e | 65 | * @param scl I2C clock line pin |
| mwilkens241 | 0:15e49005d54e | 66 | * @param scl I2C clock pin mode |
| mwilkens241 | 0:15e49005d54e | 67 | * |
| mwilkens241 | 0:15e49005d54e | 68 | * @note this is a workaround to provide a constructor which currently |
| mwilkens241 | 0:15e49005d54e | 69 | * is somehow missing in the I2C base class and it's underlying |
| mwilkens241 | 0:15e49005d54e | 70 | * implementations. In some circumstances (e.g. while debugging) |
| mwilkens241 | 0:15e49005d54e | 71 | * where long latencies between the initialization of the i2c |
| mwilkens241 | 0:15e49005d54e | 72 | * interface in the I2C constructor and the setting of the pin |
| mwilkens241 | 0:15e49005d54e | 73 | * modes in the beyond constructor might occur, the i2c |
| mwilkens241 | 0:15e49005d54e | 74 | * communication might be compromised. |
| mwilkens241 | 0:15e49005d54e | 75 | */ |
| mwilkens241 | 0:15e49005d54e | 76 | DevI2C(PinName sda, int mode_sda, PinName scl, int mode_scl) : I2C(sda, scl) { |
| mwilkens241 | 0:15e49005d54e | 77 | pin_mode(sda, (PinMode)mode_sda); |
| mwilkens241 | 0:15e49005d54e | 78 | pin_mode(scl, (PinMode)mode_scl); |
| mwilkens241 | 0:15e49005d54e | 79 | } |
| mwilkens241 | 0:15e49005d54e | 80 | |
| mwilkens241 | 0:15e49005d54e | 81 | /** |
| mwilkens241 | 0:15e49005d54e | 82 | * @brief Writes a buffer towards the I2C peripheral device. |
| mwilkens241 | 0:15e49005d54e | 83 | * @param pBuffer pointer to the byte-array data to send |
| mwilkens241 | 0:15e49005d54e | 84 | * @param DeviceAddr specifies the peripheral device slave address. |
| mwilkens241 | 0:15e49005d54e | 85 | * @param RegisterAddr specifies the internal address register |
| mwilkens241 | 0:15e49005d54e | 86 | * where to start writing to (must be correctly masked). |
| mwilkens241 | 0:15e49005d54e | 87 | * @param NumByteToWrite number of bytes to be written. |
| mwilkens241 | 0:15e49005d54e | 88 | * @retval 0 if ok, |
| mwilkens241 | 0:15e49005d54e | 89 | * @retval -1 if an I2C error has occured, or |
| mwilkens241 | 0:15e49005d54e | 90 | * @retval -2 on temporary buffer overflow (i.e. NumByteToWrite was too high) |
| mwilkens241 | 0:15e49005d54e | 91 | * @note On some devices if NumByteToWrite is greater |
| mwilkens241 | 0:15e49005d54e | 92 | * than one, the RegisterAddr must be masked correctly! |
| mwilkens241 | 0:15e49005d54e | 93 | */ |
| mwilkens241 | 0:15e49005d54e | 94 | int i2c_write(uint8_t* pBuffer, uint8_t DeviceAddr, uint8_t RegisterAddr, |
| mwilkens241 | 0:15e49005d54e | 95 | uint16_t NumByteToWrite) { |
| mwilkens241 | 0:15e49005d54e | 96 | int ret; |
| mwilkens241 | 0:15e49005d54e | 97 | uint8_t tmp[TEMP_BUF_SIZE]; |
| mwilkens241 | 0:15e49005d54e | 98 | |
| mwilkens241 | 0:15e49005d54e | 99 | if(NumByteToWrite >= TEMP_BUF_SIZE) return -2; |
| mwilkens241 | 0:15e49005d54e | 100 | |
| mwilkens241 | 0:15e49005d54e | 101 | /* First, send device address. Then, send data and STOP condition */ |
| mwilkens241 | 0:15e49005d54e | 102 | tmp[0] = RegisterAddr; |
| mwilkens241 | 0:15e49005d54e | 103 | memcpy(tmp+1, pBuffer, NumByteToWrite); |
| mwilkens241 | 0:15e49005d54e | 104 | |
| mwilkens241 | 0:15e49005d54e | 105 | ret = write(DeviceAddr, (const char*)tmp, NumByteToWrite+1, false); |
| mwilkens241 | 0:15e49005d54e | 106 | |
| mwilkens241 | 0:15e49005d54e | 107 | if(ret) return -1; |
| mwilkens241 | 0:15e49005d54e | 108 | return 0; |
| mwilkens241 | 0:15e49005d54e | 109 | } |
| mwilkens241 | 0:15e49005d54e | 110 | |
| mwilkens241 | 0:15e49005d54e | 111 | /** |
| mwilkens241 | 0:15e49005d54e | 112 | * @brief Reads a buffer from the I2C peripheral device. |
| mwilkens241 | 0:15e49005d54e | 113 | * @param pBuffer pointer to the byte-array to read data in to |
| mwilkens241 | 0:15e49005d54e | 114 | * @param DaviceAddr specifies the peripheral device slave address. |
| mwilkens241 | 0:15e49005d54e | 115 | * @param RegisterAddr specifies the internal address register |
| mwilkens241 | 0:15e49005d54e | 116 | * where to start reading from (must be correctly masked). |
| mwilkens241 | 0:15e49005d54e | 117 | * @param NumByteToRead number of bytes to be read. |
| mwilkens241 | 0:15e49005d54e | 118 | * @retval 0 if ok, |
| mwilkens241 | 0:15e49005d54e | 119 | * @retval -1 if an I2C error has occured |
| mwilkens241 | 0:15e49005d54e | 120 | * @note On some devices if NumByteToWrite is greater |
| mwilkens241 | 0:15e49005d54e | 121 | * than one, the RegisterAddr must be masked correctly! |
| mwilkens241 | 0:15e49005d54e | 122 | */ |
| mwilkens241 | 0:15e49005d54e | 123 | int i2c_read(uint8_t* pBuffer, uint8_t DeviceAddr, uint8_t RegisterAddr, |
| mwilkens241 | 0:15e49005d54e | 124 | uint16_t NumByteToRead) { |
| mwilkens241 | 0:15e49005d54e | 125 | int ret; |
| mwilkens241 | 0:15e49005d54e | 126 | |
| mwilkens241 | 0:15e49005d54e | 127 | /* Send device address, with no STOP condition */ |
| mwilkens241 | 0:15e49005d54e | 128 | ret = write(DeviceAddr, (const char*)&RegisterAddr, 1, true); |
| mwilkens241 | 0:15e49005d54e | 129 | if(!ret) { |
| mwilkens241 | 0:15e49005d54e | 130 | /* Read data, with STOP condition */ |
| mwilkens241 | 0:15e49005d54e | 131 | ret = read(DeviceAddr, (char*)pBuffer, NumByteToRead, false); |
| mwilkens241 | 0:15e49005d54e | 132 | } |
| mwilkens241 | 0:15e49005d54e | 133 | |
| mwilkens241 | 0:15e49005d54e | 134 | if(ret) return -1; |
| mwilkens241 | 0:15e49005d54e | 135 | return 0; |
| mwilkens241 | 0:15e49005d54e | 136 | } |
| mwilkens241 | 0:15e49005d54e | 137 | |
| mwilkens241 | 0:15e49005d54e | 138 | private: |
| mwilkens241 | 0:15e49005d54e | 139 | static const unsigned int TEMP_BUF_SIZE = 32; |
| mwilkens241 | 0:15e49005d54e | 140 | }; |
| mwilkens241 | 0:15e49005d54e | 141 | |
| mwilkens241 | 0:15e49005d54e | 142 | #endif /* __DEV_I2C_H */ |