Tsungta Wu
/
mbed_SPIS_multiByte_example_SOG
fork from Sog
Fork of mbed_SPIS_multiByte_example_SOG by
Diff: SPISlave_multiByte.h
- Revision:
- 0:b7415ae44dac
- Child:
- 2:c520d7c7739d
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/SPISlave_multiByte.h Wed May 24 10:17:56 2017 +0000 @@ -0,0 +1,124 @@ +/* mbed Microcontroller Library + * Copyright (c) 2006-2013 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_SPISLAVE_MULTIBYTE_H +#define MBED_SPISLAVE_MULTIBYTE_H + +#include "platform/platform.h" + +#if DEVICE_SPISLAVE + +#include "spi_api_multibyte.h" + +namespace mbed { + +/** A SPI slave, used for communicating with a SPI Master device + * + * The default format is set to 8-bits, mode 0, and a clock frequency of 1MHz + * + * @Note Synchronization level: Not protected + * + * Example: + * @code + * // Reply to a SPI master as slave + * + * #include "mbed.h" + * + * SPISlave device(p5, p6, p7, p8); // mosi, miso, sclk, ssel + * + * int main() { + * device.reply(0x00); // Prime SPI with first reply + * while(1) { + * if(device.receive()) { + * int v = device.read(); // Read byte from master + * v = (v + 1) % 0x100; // Add one to it, modulo 256 + * device.reply(v); // Make this the next reply + * } + * } + * } + * @endcode + */ +class SPISlave_multiByte { + +public: + + /** Create a SPI slave 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 + */ + SPISlave_multiByte(PinName mosi, PinName miso, PinName sclk, PinName ssel); + + /** 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); + + /** Polls the SPI to see if data has been received + * + * @returns + * 0 if no data, + * 1 otherwise + */ + int receive(void); + + /** Retrieve data from receive buffer as slave + * + * @returns + * the data in the receive buffer + */ + int read(void); + + /** Fill the transmission buffer with the value to be written out + * as slave on the next received message from the master. + * + * @param value the data to be transmitted next + */ + void reply(int value); + +protected: + spi_mb_t _spi; + + int _bits; + int _mode; + int _hz; +}; + +} // namespace mbed + +#endif + +#endif \ No newline at end of file