ST Expansion SW Team
/
X_NUCLEO_COMMON_SPI3W
Important changes to repositories hosted on mbed.com
Mbed hosted mercurial repositories are deprecated and are due to be permanently deleted in July 2026.
To keep a copy of this software download the repository Zip archive or clone locally using Mercurial.
It is also possible to export all your personal repositories from the account settings page.
Fork of
X_NUCLEO_COMMON_SPI3W
by 
Licio Mapelli
DevSPI/DevSPI.h@15:a59f32439f9d, 2016-02-19 (annotated)
- Committer:
- Wolfgang Betz
- Date:
- Fri Feb 19 09:33:04 2016 +0100
- Revision:
- 15:a59f32439f9d
- Parent:
- 14:7e8db11e12c7
- Child:
- 16:216930edb6b7
- Child:
- 17:99d103ca04dd
Correct 16-bit support
Who changed what in which revision?
| User | Revision | Line number | New contents of line |
|---|---|---|---|
| Wolfgang Betz |
12:fb6321e37154 | 1 | /** |
| Wolfgang Betz |
12:fb6321e37154 | 2 | ****************************************************************************** |
| Wolfgang Betz |
12:fb6321e37154 | 3 | * @file DevSPI.h |
| Wolfgang Betz |
15:a59f32439f9d | 4 | * @author AST / Software Platforms and Cloud / EST |
| Wolfgang Betz |
15:a59f32439f9d | 5 | * @version V1.2.1 |
| Wolfgang Betz |
15:a59f32439f9d | 6 | * @date 19-February-2016 |
| Wolfgang Betz |
12:fb6321e37154 | 7 | * @brief Header file for a special SPI class DevSPI which provides some |
| Wolfgang Betz |
15:a59f32439f9d | 8 | * helper functions for on-board communication. |
| Wolfgang Betz |
12:fb6321e37154 | 9 | ****************************************************************************** |
| Wolfgang Betz |
12:fb6321e37154 | 10 | * @attention |
| Wolfgang Betz |
12:fb6321e37154 | 11 | * |
| Wolfgang Betz |
15:a59f32439f9d | 12 | * <h2><center>© COPYRIGHT(c) 2016 STMicroelectronics</center></h2> |
| Wolfgang Betz |
12:fb6321e37154 | 13 | * |
| Wolfgang Betz |
12:fb6321e37154 | 14 | * Redistribution and use in source and binary forms, with or without modification, |
| Wolfgang Betz |
12:fb6321e37154 | 15 | * are permitted provided that the following conditions are met: |
| Wolfgang Betz |
12:fb6321e37154 | 16 | * 1. Redistributions of source code must retain the above copyright notice, |
| Wolfgang Betz |
12:fb6321e37154 | 17 | * this list of conditions and the following disclaimer. |
| Wolfgang Betz |
12:fb6321e37154 | 18 | * 2. Redistributions in binary form must reproduce the above copyright notice, |
| Wolfgang Betz |
12:fb6321e37154 | 19 | * this list of conditions and the following disclaimer in the documentation |
| Wolfgang Betz |
12:fb6321e37154 | 20 | * and/or other materials provided with the distribution. |
| Wolfgang Betz |
12:fb6321e37154 | 21 | * 3. Neither the name of STMicroelectronics nor the names of its contributors |
| Wolfgang Betz |
12:fb6321e37154 | 22 | * may be used to endorse or promote products derived from this software |
| Wolfgang Betz |
12:fb6321e37154 | 23 | * without specific prior written permission. |
| Wolfgang Betz |
12:fb6321e37154 | 24 | * |
| Wolfgang Betz |
12:fb6321e37154 | 25 | * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" |
| Wolfgang Betz |
12:fb6321e37154 | 26 | * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| Wolfgang Betz |
12:fb6321e37154 | 27 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE |
| Wolfgang Betz |
12:fb6321e37154 | 28 | * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE |
| Wolfgang Betz |
12:fb6321e37154 | 29 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| Wolfgang Betz |
12:fb6321e37154 | 30 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR |
| Wolfgang Betz |
12:fb6321e37154 | 31 | * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER |
| Wolfgang Betz |
12:fb6321e37154 | 32 | * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, |
| Wolfgang Betz |
12:fb6321e37154 | 33 | * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| Wolfgang Betz |
12:fb6321e37154 | 34 | * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| Wolfgang Betz |
12:fb6321e37154 | 35 | * |
| Wolfgang Betz |
12:fb6321e37154 | 36 | ****************************************************************************** |
| Wolfgang Betz |
12:fb6321e37154 | 37 | */ |
| Wolfgang Betz |
12:fb6321e37154 | 38 | |
| Wolfgang Betz |
12:fb6321e37154 | 39 | /* Define to prevent from recursive inclusion --------------------------------*/ |
| Wolfgang Betz |
12:fb6321e37154 | 40 | #ifndef __DEV_SPI_H |
| Wolfgang Betz |
12:fb6321e37154 | 41 | #define __DEV_SPI_H |
| Wolfgang Betz |
12:fb6321e37154 | 42 | |
| Wolfgang Betz |
12:fb6321e37154 | 43 | /* Includes ------------------------------------------------------------------*/ |
| Wolfgang Betz |
12:fb6321e37154 | 44 | #include "mbed.h" |
| Wolfgang Betz |
12:fb6321e37154 | 45 | |
| Wolfgang Betz |
15:a59f32439f9d | 46 | /* Macros --------------------------------------------------------------------*/ |
| Wolfgang Betz |
15:a59f32439f9d | 47 | #if (defined(__BYTE_ORDER__) && (__BYTE_ORDER__ == __ORDER_BIG_ENDIAN__)) /* GCC */ || \ |
| Wolfgang Betz |
15:a59f32439f9d | 48 | (defined(G_BYTE_ORDER) && (G_BYTE_ORDER == G_BIG_ENDIAN)) /* IAR */ || \ |
| Wolfgang Betz |
15:a59f32439f9d | 49 | (defined(__BIG_ENDIAN)) /* ARM */ |
| Wolfgang Betz |
15:a59f32439f9d | 50 | #define __DEV_SPI_BIG_ENDIAN |
| Wolfgang Betz |
15:a59f32439f9d | 51 | #endif |
| Wolfgang Betz |
15:a59f32439f9d | 52 | |
| Wolfgang Betz |
12:fb6321e37154 | 53 | /* Classes -------------------------------------------------------------------*/ |
| Wolfgang Betz |
15:a59f32439f9d | 54 | /** Helper class DevSPI providing functions for synchronous SPI communication |
| Wolfgang Betz |
15:a59f32439f9d | 55 | * common for a series of SPI devices. |
| Wolfgang Betz |
12:fb6321e37154 | 56 | */ |
| Wolfgang Betz |
12:fb6321e37154 | 57 | class DevSPI : public SPI |
| Wolfgang Betz |
12:fb6321e37154 | 58 | { |
| Wolfgang Betz |
15:a59f32439f9d | 59 | public: |
| Wolfgang Betz |
12:fb6321e37154 | 60 | /* |
| Wolfgang Betz |
12:fb6321e37154 | 61 | * Create a DevSPI interface. |
| Wolfgang Betz |
12:fb6321e37154 | 62 | * @param mosi pin name of the MOSI pin of the SPI device to be used for communication. |
| Wolfgang Betz |
12:fb6321e37154 | 63 | * @param miso pin name of the MISO pin of the SPI device to be used for communication. |
| Wolfgang Betz |
12:fb6321e37154 | 64 | * @param sclk pin name of the SCLK pin of the SPI device to be used for communication. |
| Wolfgang Betz |
12:fb6321e37154 | 65 | */ |
| Wolfgang Betz |
15:a59f32439f9d | 66 | DevSPI(PinName mosi, PinName miso, PinName sclk) : SPI(mosi, miso, sclk) |
| Wolfgang Betz |
12:fb6321e37154 | 67 | { |
| Wolfgang Betz |
14:7e8db11e12c7 | 68 | /* Set default configuration. */ |
| Wolfgang Betz |
14:7e8db11e12c7 | 69 | setup(8, 3, 1E6); |
| Wolfgang Betz |
12:fb6321e37154 | 70 | } |
| Wolfgang Betz |
12:fb6321e37154 | 71 | |
| Wolfgang Betz |
12:fb6321e37154 | 72 | /* |
| Wolfgang Betz |
12:fb6321e37154 | 73 | * Setup the spi. |
| Wolfgang Betz |
12:fb6321e37154 | 74 | * Typically: |
| Wolfgang Betz |
12:fb6321e37154 | 75 | * + 8 bit data; |
| Wolfgang Betz |
12:fb6321e37154 | 76 | * + high steady state clock; |
| Wolfgang Betz |
12:fb6321e37154 | 77 | * + second edge capture; |
| Wolfgang Betz |
12:fb6321e37154 | 78 | * + 1MHz clock rate. |
| Wolfgang Betz |
12:fb6321e37154 | 79 | * |
| Wolfgang Betz |
12:fb6321e37154 | 80 | * @param bits Number of bits per SPI frame (4 - 16) |
| Wolfgang Betz |
12:fb6321e37154 | 81 | * @param mode Clock polarity and phase mode (0 - 3) |
| Wolfgang Betz |
12:fb6321e37154 | 82 | * @param frequency_hz SCLK frequency in hz (default = 1MHz) |
| Wolfgang Betz |
12:fb6321e37154 | 83 | * |
| Wolfgang Betz |
12:fb6321e37154 | 84 | * @code |
| Wolfgang Betz |
12:fb6321e37154 | 85 | * mode | POL PHA |
| Wolfgang Betz |
12:fb6321e37154 | 86 | * -----+-------- |
| Wolfgang Betz |
12:fb6321e37154 | 87 | * 0 | 0 0 |
| Wolfgang Betz |
12:fb6321e37154 | 88 | * 1 | 0 1 |
| Wolfgang Betz |
12:fb6321e37154 | 89 | * 2 | 1 0 |
| Wolfgang Betz |
12:fb6321e37154 | 90 | * 3 | 1 1 |
| Wolfgang Betz |
12:fb6321e37154 | 91 | * @endcode |
| Wolfgang Betz |
12:fb6321e37154 | 92 | */ |
| Wolfgang Betz |
12:fb6321e37154 | 93 | void setup(int bits, int mode = 0, int frequency_hz = 1E6) |
| Wolfgang Betz |
12:fb6321e37154 | 94 | { |
| Wolfgang Betz |
14:7e8db11e12c7 | 95 | /* Set given configuration. */ |
| Wolfgang Betz |
12:fb6321e37154 | 96 | format(bits, mode); |
| Wolfgang Betz |
12:fb6321e37154 | 97 | frequency(frequency_hz); |
| Wolfgang Betz |
15:a59f32439f9d | 98 | } |
| Wolfgang Betz |
12:fb6321e37154 | 99 | |
| Wolfgang Betz |
12:fb6321e37154 | 100 | /** |
| Wolfgang Betz |
15:a59f32439f9d | 101 | * @brief Writes a buffer to the SPI peripheral device in 8-bit data mode |
| Wolfgang Betz |
15:a59f32439f9d | 102 | * using synchronous SPI communication. |
| Wolfgang Betz |
12:fb6321e37154 | 103 | * @param[in] pBuffer pointer to the buffer of data to send. |
| Wolfgang Betz |
12:fb6321e37154 | 104 | * @param[in] ssel GPIO of the SSEL pin of the SPI device to be used for communication. |
| Wolfgang Betz |
12:fb6321e37154 | 105 | * @param[in] NumBytesToWrite number of bytes to write. |
| Wolfgang Betz |
12:fb6321e37154 | 106 | * @retval 0 if ok. |
| Wolfgang Betz |
15:a59f32439f9d | 107 | * @retval -1 if data format error. |
| Wolfgang Betz |
12:fb6321e37154 | 108 | * @note When using the SPI in Interrupt-mode, remember to disable interrupts |
| Wolfgang Betz |
12:fb6321e37154 | 109 | * before calling this function and to enable them again after. |
| Wolfgang Betz |
12:fb6321e37154 | 110 | */ |
| Wolfgang Betz |
12:fb6321e37154 | 111 | int spi_write(uint8_t* pBuffer, DigitalOut ssel, uint16_t NumBytesToWrite) |
| Wolfgang Betz |
12:fb6321e37154 | 112 | { |
| Wolfgang Betz |
15:a59f32439f9d | 113 | /* Check data format */ |
| Wolfgang Betz |
15:a59f32439f9d | 114 | if(_bits != 8) return -1; |
| Wolfgang Betz |
15:a59f32439f9d | 115 | |
| Wolfgang Betz |
12:fb6321e37154 | 116 | /* Select the chip. */ |
| Wolfgang Betz |
12:fb6321e37154 | 117 | ssel = 0; |
| Wolfgang Betz |
12:fb6321e37154 | 118 | |
| Wolfgang Betz |
12:fb6321e37154 | 119 | /* Write data. */ |
| Wolfgang Betz |
15:a59f32439f9d | 120 | for (int i = 0; i < NumBytesToWrite; i++) { |
| Wolfgang Betz |
15:a59f32439f9d | 121 | write(pBuffer[i]); |
| Wolfgang Betz |
15:a59f32439f9d | 122 | } |
| Wolfgang Betz |
15:a59f32439f9d | 123 | |
| Wolfgang Betz |
15:a59f32439f9d | 124 | /* Unselect the chip. */ |
| Wolfgang Betz |
15:a59f32439f9d | 125 | ssel = 1; |
| Wolfgang Betz |
15:a59f32439f9d | 126 | |
| Wolfgang Betz |
15:a59f32439f9d | 127 | return 0; |
| Wolfgang Betz |
15:a59f32439f9d | 128 | } |
| Wolfgang Betz |
15:a59f32439f9d | 129 | |
| Wolfgang Betz |
15:a59f32439f9d | 130 | /** |
| Wolfgang Betz |
15:a59f32439f9d | 131 | * @brief Reads a buffer from the SPI peripheral device in 8-bit data mode |
| Wolfgang Betz |
15:a59f32439f9d | 132 | * using synchronous SPI communication. |
| Wolfgang Betz |
15:a59f32439f9d | 133 | * @param[out] pBuffer pointer to the buffer to read data into. |
| Wolfgang Betz |
15:a59f32439f9d | 134 | * @param[in] ssel GPIO of the SSEL pin of the SPI device to be used for communication. |
| Wolfgang Betz |
15:a59f32439f9d | 135 | * @param[in] NumBytesToRead number of bytes to read. |
| Wolfgang Betz |
15:a59f32439f9d | 136 | * @retval 0 if ok. |
| Wolfgang Betz |
15:a59f32439f9d | 137 | * @retval -1 if data format error. |
| Wolfgang Betz |
15:a59f32439f9d | 138 | * @note When using the SPI in Interrupt-mode, remember to disable interrupts |
| Wolfgang Betz |
15:a59f32439f9d | 139 | * before calling this function and to enable them again after. |
| Wolfgang Betz |
15:a59f32439f9d | 140 | */ |
| Wolfgang Betz |
15:a59f32439f9d | 141 | int spi_read(uint8_t* pBuffer, DigitalOut ssel, uint16_t NumBytesToRead) |
| Wolfgang Betz |
15:a59f32439f9d | 142 | { |
| Wolfgang Betz |
15:a59f32439f9d | 143 | /* Check data format */ |
| Wolfgang Betz |
15:a59f32439f9d | 144 | if(_bits != 8) return -1; |
| Wolfgang Betz |
15:a59f32439f9d | 145 | |
| Wolfgang Betz |
15:a59f32439f9d | 146 | /* Select the chip. */ |
| Wolfgang Betz |
15:a59f32439f9d | 147 | ssel = 0; |
| Wolfgang Betz |
15:a59f32439f9d | 148 | |
| Wolfgang Betz |
15:a59f32439f9d | 149 | /* Read data. */ |
| Wolfgang Betz |
15:a59f32439f9d | 150 | for (int i = 0; i < NumBytesToRead; i++) { |
| Wolfgang Betz |
15:a59f32439f9d | 151 | pBuffer[i] = write(0); |
| Wolfgang Betz |
15:a59f32439f9d | 152 | } |
| Wolfgang Betz |
15:a59f32439f9d | 153 | |
| Wolfgang Betz |
15:a59f32439f9d | 154 | /* Unselect the chip. */ |
| Wolfgang Betz |
15:a59f32439f9d | 155 | ssel = 1; |
| Wolfgang Betz |
15:a59f32439f9d | 156 | |
| Wolfgang Betz |
15:a59f32439f9d | 157 | return 0; |
| Wolfgang Betz |
15:a59f32439f9d | 158 | } |
| Wolfgang Betz |
15:a59f32439f9d | 159 | |
| Wolfgang Betz |
15:a59f32439f9d | 160 | /** |
| Wolfgang Betz |
15:a59f32439f9d | 161 | * @brief Reads and write a buffer from/to the SPI peripheral device at the same time |
| Wolfgang Betz |
15:a59f32439f9d | 162 | * in 8-bit data mode using synchronous SPI communication. |
| Wolfgang Betz |
15:a59f32439f9d | 163 | * @param[out] pBufferToRead pointer to the buffer to read data into. |
| Wolfgang Betz |
15:a59f32439f9d | 164 | * @param[in] pBufferToWrite pointer to the buffer of data to send. |
| Wolfgang Betz |
15:a59f32439f9d | 165 | * @param[in] ssel GPIO of the SSEL pin of the SPI device to be used for communication. |
| Wolfgang Betz |
15:a59f32439f9d | 166 | * @param[in] NumBytes number of bytes to read and write. |
| Wolfgang Betz |
15:a59f32439f9d | 167 | * @retval 0 if ok. |
| Wolfgang Betz |
15:a59f32439f9d | 168 | * @retval -1 if data format error. |
| Wolfgang Betz |
15:a59f32439f9d | 169 | * @note When using the SPI in Interrupt-mode, remember to disable interrupts |
| Wolfgang Betz |
15:a59f32439f9d | 170 | * before calling this function and to enable them again after. |
| Wolfgang Betz |
15:a59f32439f9d | 171 | */ |
| Wolfgang Betz |
15:a59f32439f9d | 172 | int spi_read_write(uint8_t* pBufferToRead, uint8_t* pBufferToWrite, DigitalOut ssel, uint16_t NumBytes) |
| Wolfgang Betz |
15:a59f32439f9d | 173 | { |
| Wolfgang Betz |
15:a59f32439f9d | 174 | /* Check data format */ |
| Wolfgang Betz |
15:a59f32439f9d | 175 | if(_bits != 8) return -1; |
| Wolfgang Betz |
15:a59f32439f9d | 176 | |
| Wolfgang Betz |
15:a59f32439f9d | 177 | /* Select the chip. */ |
| Wolfgang Betz |
15:a59f32439f9d | 178 | ssel = 0; |
| Wolfgang Betz |
15:a59f32439f9d | 179 | |
| Wolfgang Betz |
15:a59f32439f9d | 180 | /* Read and write data at the same time. */ |
| Wolfgang Betz |
15:a59f32439f9d | 181 | for (int i = 0; i < NumBytes; i++) { |
| Wolfgang Betz |
15:a59f32439f9d | 182 | pBufferToRead[i] = write(pBufferToWrite[i]); |
| Wolfgang Betz |
15:a59f32439f9d | 183 | } |
| Wolfgang Betz |
12:fb6321e37154 | 184 | |
| Wolfgang Betz |
12:fb6321e37154 | 185 | /* Unselect the chip. */ |
| Wolfgang Betz |
12:fb6321e37154 | 186 | ssel = 1; |
| Wolfgang Betz |
12:fb6321e37154 | 187 | |
| Wolfgang Betz |
12:fb6321e37154 | 188 | return 0; |
| Wolfgang Betz |
12:fb6321e37154 | 189 | } |
| Wolfgang Betz |
12:fb6321e37154 | 190 | |
| Wolfgang Betz |
12:fb6321e37154 | 191 | /** |
| Wolfgang Betz |
15:a59f32439f9d | 192 | * @brief Writes a buffer to the SPI peripheral device in 16-bit data mode |
| Wolfgang Betz |
15:a59f32439f9d | 193 | * using synchronous SPI communication. |
| Wolfgang Betz |
15:a59f32439f9d | 194 | * @param[in] pBuffer pointer to the buffer of data to send. |
| Wolfgang Betz |
12:fb6321e37154 | 195 | * @param[in] ssel GPIO of the SSEL pin of the SPI device to be used for communication. |
| Wolfgang Betz |
15:a59f32439f9d | 196 | * @param[in] NumValuesToWrite number of 16-bit values to write. |
| Wolfgang Betz |
12:fb6321e37154 | 197 | * @retval 0 if ok. |
| Wolfgang Betz |
15:a59f32439f9d | 198 | * @retval -1 if data format error. |
| Wolfgang Betz |
12:fb6321e37154 | 199 | * @note When using the SPI in Interrupt-mode, remember to disable interrupts |
| Wolfgang Betz |
12:fb6321e37154 | 200 | * before calling this function and to enable them again after. |
| Wolfgang Betz |
15:a59f32439f9d | 201 | * @note In order to guarantee this method to work correctly you have to |
| Wolfgang Betz |
15:a59f32439f9d | 202 | * pass buffers which are correctly aligned. |
| Wolfgang Betz |
12:fb6321e37154 | 203 | */ |
| Wolfgang Betz |
15:a59f32439f9d | 204 | int spi_write(uint16_t* pBuffer, DigitalOut ssel, uint16_t NumValuesToWrite) |
| Wolfgang Betz |
12:fb6321e37154 | 205 | { |
| Wolfgang Betz |
15:a59f32439f9d | 206 | /* Check data format */ |
| Wolfgang Betz |
15:a59f32439f9d | 207 | if(_bits != 16) return -1; |
| Wolfgang Betz |
15:a59f32439f9d | 208 | |
| Wolfgang Betz |
12:fb6321e37154 | 209 | /* Select the chip. */ |
| Wolfgang Betz |
12:fb6321e37154 | 210 | ssel = 0; |
| Wolfgang Betz |
12:fb6321e37154 | 211 | |
| Wolfgang Betz |
15:a59f32439f9d | 212 | /* Write data. */ |
| Wolfgang Betz |
15:a59f32439f9d | 213 | for (int i = 0; i < NumValuesToWrite; i++) { |
| Wolfgang Betz |
15:a59f32439f9d | 214 | write(htons(pBuffer[i])); |
| Wolfgang Betz |
15:a59f32439f9d | 215 | } |
| Wolfgang Betz |
12:fb6321e37154 | 216 | |
| Wolfgang Betz |
12:fb6321e37154 | 217 | /* Unselect the chip. */ |
| Wolfgang Betz |
12:fb6321e37154 | 218 | ssel = 1; |
| Wolfgang Betz |
12:fb6321e37154 | 219 | |
| Wolfgang Betz |
12:fb6321e37154 | 220 | return 0; |
| Wolfgang Betz |
12:fb6321e37154 | 221 | } |
| Wolfgang Betz |
12:fb6321e37154 | 222 | |
| Wolfgang Betz |
12:fb6321e37154 | 223 | /** |
| Wolfgang Betz |
15:a59f32439f9d | 224 | * @brief Reads a buffer from the SPI peripheral device in 16-bit data mode |
| Wolfgang Betz |
15:a59f32439f9d | 225 | * using synchronous SPI communication. |
| Wolfgang Betz |
15:a59f32439f9d | 226 | * @param[out] pBuffer pointer to the buffer to read data into. |
| Wolfgang Betz |
12:fb6321e37154 | 227 | * @param[in] ssel GPIO of the SSEL pin of the SPI device to be used for communication. |
| Wolfgang Betz |
15:a59f32439f9d | 228 | * @param[in] NumValuesToRead number of 16-bit values to read. |
| Wolfgang Betz |
12:fb6321e37154 | 229 | * @retval 0 if ok. |
| Wolfgang Betz |
15:a59f32439f9d | 230 | * @retval -1 if data format error. |
| Wolfgang Betz |
12:fb6321e37154 | 231 | * @note When using the SPI in Interrupt-mode, remember to disable interrupts |
| Wolfgang Betz |
12:fb6321e37154 | 232 | * before calling this function and to enable them again after. |
| Wolfgang Betz |
15:a59f32439f9d | 233 | * @note In order to guarantee this method to work correctly you have to |
| Wolfgang Betz |
15:a59f32439f9d | 234 | * pass buffers which are correctly aligned. |
| Wolfgang Betz |
12:fb6321e37154 | 235 | */ |
| Wolfgang Betz |
15:a59f32439f9d | 236 | int spi_read(uint16_t* pBuffer, DigitalOut ssel, uint16_t NumValuesToRead) |
| Wolfgang Betz |
12:fb6321e37154 | 237 | { |
| Wolfgang Betz |
15:a59f32439f9d | 238 | /* Check data format */ |
| Wolfgang Betz |
15:a59f32439f9d | 239 | if(_bits != 16) return -1; |
| Wolfgang Betz |
15:a59f32439f9d | 240 | |
| Wolfgang Betz |
12:fb6321e37154 | 241 | /* Select the chip. */ |
| Wolfgang Betz |
12:fb6321e37154 | 242 | ssel = 0; |
| Wolfgang Betz |
12:fb6321e37154 | 243 | |
| Wolfgang Betz |
15:a59f32439f9d | 244 | /* Read data. */ |
| Wolfgang Betz |
15:a59f32439f9d | 245 | for (int i = 0; i < NumValuesToRead; i++) { |
| Wolfgang Betz |
15:a59f32439f9d | 246 | pBuffer[i] = ntohs((uint16_t)write(0)); |
| Wolfgang Betz |
15:a59f32439f9d | 247 | } |
| Wolfgang Betz |
12:fb6321e37154 | 248 | |
| Wolfgang Betz |
12:fb6321e37154 | 249 | /* Unselect the chip. */ |
| Wolfgang Betz |
12:fb6321e37154 | 250 | ssel = 1; |
| Wolfgang Betz |
12:fb6321e37154 | 251 | |
| Wolfgang Betz |
12:fb6321e37154 | 252 | return 0; |
| Wolfgang Betz |
12:fb6321e37154 | 253 | } |
| Wolfgang Betz |
15:a59f32439f9d | 254 | |
| Wolfgang Betz |
15:a59f32439f9d | 255 | /** |
| Wolfgang Betz |
15:a59f32439f9d | 256 | * @brief Reads and write a buffer from/to the SPI peripheral device at the same time |
| Wolfgang Betz |
15:a59f32439f9d | 257 | * in 16-bit data mode using synchronous SPI communication. |
| Wolfgang Betz |
15:a59f32439f9d | 258 | * @param[out] pBufferToRead pointer to the buffer to read data into. |
| Wolfgang Betz |
15:a59f32439f9d | 259 | * @param[in] pBufferToWrite pointer to the buffer of data to send. |
| Wolfgang Betz |
15:a59f32439f9d | 260 | * @param[in] ssel GPIO of the SSEL pin of the SPI device to be used for communication. |
| Wolfgang Betz |
15:a59f32439f9d | 261 | * @param[in] NumValues number of 16-bit values to read and write. |
| Wolfgang Betz |
15:a59f32439f9d | 262 | * @retval 0 if ok. |
| Wolfgang Betz |
15:a59f32439f9d | 263 | * @retval -1 if data format error. |
| Wolfgang Betz |
15:a59f32439f9d | 264 | * @note When using the SPI in Interrupt-mode, remember to disable interrupts |
| Wolfgang Betz |
15:a59f32439f9d | 265 | * before calling this function and to enable them again after. |
| Wolfgang Betz |
15:a59f32439f9d | 266 | * @note In order to guarantee this method to work correctly you have to |
| Wolfgang Betz |
15:a59f32439f9d | 267 | * pass buffers which are correctly aligned. |
| Wolfgang Betz |
15:a59f32439f9d | 268 | */ |
| Wolfgang Betz |
15:a59f32439f9d | 269 | int spi_read_write(uint16_t* pBufferToRead, uint16_t* pBufferToWrite, DigitalOut ssel, uint16_t NumValues) |
| Wolfgang Betz |
15:a59f32439f9d | 270 | { |
| Wolfgang Betz |
15:a59f32439f9d | 271 | /* Check data format */ |
| Wolfgang Betz |
15:a59f32439f9d | 272 | if(_bits != 16) return -1; |
| Wolfgang Betz |
15:a59f32439f9d | 273 | |
| Wolfgang Betz |
15:a59f32439f9d | 274 | /* Select the chip. */ |
| Wolfgang Betz |
15:a59f32439f9d | 275 | ssel = 0; |
| Wolfgang Betz |
15:a59f32439f9d | 276 | |
| Wolfgang Betz |
15:a59f32439f9d | 277 | /* Read and write data at the same time. */ |
| Wolfgang Betz |
15:a59f32439f9d | 278 | for (int i = 0; i < NumValues; i++) { |
| Wolfgang Betz |
15:a59f32439f9d | 279 | pBufferToRead[i] = ntohs((uint16_t)write(htons(pBufferToWrite[i]))); |
| Wolfgang Betz |
15:a59f32439f9d | 280 | } |
| Wolfgang Betz |
15:a59f32439f9d | 281 | |
| Wolfgang Betz |
15:a59f32439f9d | 282 | /* Unselect the chip. */ |
| Wolfgang Betz |
15:a59f32439f9d | 283 | ssel = 1; |
| Wolfgang Betz |
15:a59f32439f9d | 284 | |
| Wolfgang Betz |
15:a59f32439f9d | 285 | return 0; |
| Wolfgang Betz |
15:a59f32439f9d | 286 | } |
| Wolfgang Betz |
15:a59f32439f9d | 287 | |
| Wolfgang Betz |
15:a59f32439f9d | 288 | protected: |
| Wolfgang Betz |
15:a59f32439f9d | 289 | inline uint16_t htons(uint16_t x) { |
| Wolfgang Betz |
15:a59f32439f9d | 290 | #ifndef __DEV_SPI_BIG_ENDIAN |
| Wolfgang Betz |
15:a59f32439f9d | 291 | return (((x)<<8)|((x)>>8)); |
| Wolfgang Betz |
15:a59f32439f9d | 292 | #else // __DEV_SPI_BIG_ENDIAN |
| Wolfgang Betz |
15:a59f32439f9d | 293 | return (x); |
| Wolfgang Betz |
15:a59f32439f9d | 294 | #endif // __DEV_SPI_BIG_ENDIAN |
| Wolfgang Betz |
15:a59f32439f9d | 295 | } |
| Wolfgang Betz |
15:a59f32439f9d | 296 | |
| Wolfgang Betz |
15:a59f32439f9d | 297 | inline uint16_t ntohs(uint16_t x) { |
| Wolfgang Betz |
15:a59f32439f9d | 298 | return htons(x); |
| Wolfgang Betz |
15:a59f32439f9d | 299 | } |
| Wolfgang Betz |
12:fb6321e37154 | 300 | }; |
| Wolfgang Betz |
12:fb6321e37154 | 301 | |
| Wolfgang Betz |
12:fb6321e37154 | 302 | #endif /* __DEV_SPI_H */ |