fix LPC812 PWM
Fork of mbed-dev by
api/SPI.h
- Committer:
- bogdanm
- Date:
- 2015-10-01
- Revision:
- 0:9b334a45a8ff
File content as of revision 0:9b334a45a8ff:
/* mbed Microcontroller Library * Copyright (c) 2006-2015 ARM Limited * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ #ifndef MBED_SPI_H #define MBED_SPI_H #include "platform.h" #if DEVICE_SPI #include "spi_api.h" #if DEVICE_SPI_ASYNCH #include "CThunk.h" #include "dma_api.h" #include "CircularBuffer.h" #include "FunctionPointer.h" #include "Transaction.h" #endif namespace mbed { /** A SPI Master, used for communicating with SPI slave devices * * The default format is set to 8-bits, mode 0, and a clock frequency of 1MHz * * Most SPI devices will also require Chip Select and Reset signals. These * can be controlled using <DigitalOut> pins * * Example: * @code * // Send a byte to a SPI slave, and record the response * * #include "mbed.h" * * // hardware ssel (where applicable) * //SPI device(p5, p6, p7, p8); // mosi, miso, sclk, ssel * * // software ssel * SPI device(p5, p6, p7); // mosi, miso, sclk * DigitalOut cs(p8); // ssel * * int main() { * // hardware ssel (where applicable) * //int response = device.write(0xFF); * * // software ssel * cs = 0; * int response = device.write(0xFF); * cs = 1; * } * @endcode */ class SPI { public: /** Create a SPI master connected to the specified pins * * mosi or miso can be specfied as NC if not used * * @param mosi SPI Master Out, Slave In pin * @param miso SPI Master In, Slave Out pin * @param sclk SPI Clock pin * @param ssel SPI chip select pin */ SPI(PinName mosi, PinName miso, PinName sclk, PinName ssel=NC); /** Configure the data transmission format * * @param bits Number of bits per SPI frame (4 - 16) * @param mode Clock polarity and phase mode (0 - 3) * * @code * mode | POL PHA * -----+-------- * 0 | 0 0 * 1 | 0 1 * 2 | 1 0 * 3 | 1 1 * @endcode */ void format(int bits, int mode = 0); /** Set the spi bus clock frequency * * @param hz SCLK frequency in hz (default = 1MHz) */ void frequency(int hz = 1000000); /** Write to the SPI Slave and return the response * * @param value Data to be sent to the SPI slave * * @returns * Response from the SPI slave */ virtual int write(int value); #if DEVICE_SPI_ASYNCH /** Start non-blocking SPI transfer using 8bit buffers. * * @param tx_buffer The TX buffer with data to be transfered. If NULL is passed, * the default SPI value is sent * @param tx_length The length of TX buffer in bytes * @param rx_buffer The RX buffer which is used for received data. If NULL is passed, * received data are ignored * @param rx_length The length of RX buffer in bytes * @param callback The event callback function * @param event The logical OR of events to modify. Look at spi hal header file for SPI events. * @return Zero if the transfer has started, or -1 if SPI peripheral is busy */ template<typename Type> int transfer(const Type *tx_buffer, int tx_length, Type *rx_buffer, int rx_length, const event_callback_t& callback, int event = SPI_EVENT_COMPLETE) { if (spi_active(&_spi)) { return queue_transfer(tx_buffer, tx_length, rx_buffer, rx_length, sizeof(Type)*8, callback, event); } start_transfer(tx_buffer, tx_length, rx_buffer, rx_length, sizeof(Type)*8, callback, event); return 0; } /** Abort the on-going SPI transfer, and continue with transfer's in the queue if any. */ void abort_transfer(); /** Clear the transaction buffer */ void clear_transfer_buffer(); /** Clear the transaction buffer and abort on-going transfer. */ void abort_all_transfers(); /** Configure DMA usage suggestion for non-blocking transfers * * @param usage The usage DMA hint for peripheral * @return Zero if the usage was set, -1 if a transaction is on-going */ int set_dma_usage(DMAUsage usage); protected: /** SPI IRQ handler * */ void irq_handler_asynch(void); /** Common transfer method * * @param tx_buffer The TX buffer with data to be transfered. If NULL is passed, * the default SPI value is sent * @param tx_length The length of TX buffer in bytes * @param rx_buffer The RX buffer which is used for received data. If NULL is passed, * received data are ignored * @param rx_length The length of RX buffer in bytes * @param bit_width The buffers element width * @param callback The event callback function * @param event The logical OR of events to modify * @return Zero if the transfer has started or was added to the queue, or -1 if SPI peripheral is busy/buffer is full */ int transfer(const void *tx_buffer, int tx_length, void *rx_buffer, int rx_length, unsigned char bit_width, const event_callback_t& callback, int event); /** * * @param tx_buffer The TX buffer with data to be transfered. If NULL is passed, * the default SPI value is sent * @param tx_length The length of TX buffer in bytes * @param rx_buffer The RX buffer which is used for received data. If NULL is passed, * received data are ignored * @param rx_length The length of RX buffer in bytes * @param bit_width The buffers element width * @param callback The event callback function * @param event The logical OR of events to modify * @return Zero if a transfer was added to the queue, or -1 if the queue is full */ int queue_transfer(const void *tx_buffer, int tx_length, void *rx_buffer, int rx_length, unsigned char bit_width, const event_callback_t& callback, int event); /** Configures a callback, spi peripheral and initiate a new transfer * * @param tx_buffer The TX buffer with data to be transfered. If NULL is passed, * the default SPI value is sent * @param tx_length The length of TX buffer in bytes * @param rx_buffer The RX buffer which is used for received data. If NULL is passed, * received data are ignored * @param rx_length The length of RX buffer in bytes * @param bit_width The buffers element width * @param callback The event callback function * @param event The logical OR of events to modify */ void start_transfer(const void *tx_buffer, int tx_length, void *rx_buffer, int rx_length, unsigned char bit_width, const event_callback_t& callback, int event); #if TRANSACTION_QUEUE_SIZE_SPI /** Start a new transaction * * @param data Transaction data */ void start_transaction(transaction_t *data); /** Dequeue a transaction * */ void dequeue_transaction(); static CircularBuffer<Transaction<SPI>, TRANSACTION_QUEUE_SIZE_SPI> _transaction_buffer; #endif #endif public: virtual ~SPI() { } protected: spi_t _spi; #if DEVICE_SPI_ASYNCH CThunk<SPI> _irq; event_callback_t _callback; DMAUsage _usage; #endif void aquire(void); static SPI *_owner; int _bits; int _mode; int _hz; }; } // namespace mbed #endif #endif