Renato Grottesi / mbed-dev-bin

Microbit as a BLE gamepad

Dependents:   microbit-dal

Fork of mbed-dev-bin by Lancaster University

SPISlave.h@4:bb4b3734941b, 2017-01-30 (annotated)

Committer:
rengro01
Date:
Mon Jan 30 08:23:23 2017 +0000
Revision:
4:bb4b3734941b
Parent:
0:e1a608bb55e8 
Microbit as a BLE gamepad

Who changed what in which revision?

UserRevisionLine numberNew contents of line
jamesadevine 0:e1a608bb55e8 1 /* mbed Microcontroller Library
jamesadevine 0:e1a608bb55e8 2 * Copyright (c) 2006-2013 ARM Limited
jamesadevine 0:e1a608bb55e8 3 *
jamesadevine 0:e1a608bb55e8 4 * Licensed under the Apache License, Version 2.0 (the "License");
jamesadevine 0:e1a608bb55e8 5 * you may not use this file except in compliance with the License.
jamesadevine 0:e1a608bb55e8 6 * You may obtain a copy of the License at
jamesadevine 0:e1a608bb55e8 7 *
jamesadevine 0:e1a608bb55e8 8 * http://www.apache.org/licenses/LICENSE-2.0
jamesadevine 0:e1a608bb55e8 9 *
jamesadevine 0:e1a608bb55e8 10 * Unless required by applicable law or agreed to in writing, software
jamesadevine 0:e1a608bb55e8 11 * distributed under the License is distributed on an "AS IS" BASIS,
jamesadevine 0:e1a608bb55e8 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
jamesadevine 0:e1a608bb55e8 13 * See the License for the specific language governing permissions and
jamesadevine 0:e1a608bb55e8 14 * limitations under the License.
jamesadevine 0:e1a608bb55e8 15 */
jamesadevine 0:e1a608bb55e8 16 #ifndef MBED_SPISLAVE_H
jamesadevine 0:e1a608bb55e8 17 #define MBED_SPISLAVE_H
jamesadevine 0:e1a608bb55e8 18
jamesadevine 0:e1a608bb55e8 19 #include "platform.h"
jamesadevine 0:e1a608bb55e8 20
jamesadevine 0:e1a608bb55e8 21 #if DEVICE_SPISLAVE
jamesadevine 0:e1a608bb55e8 22
jamesadevine 0:e1a608bb55e8 23 #include "spi_api.h"
jamesadevine 0:e1a608bb55e8 24
jamesadevine 0:e1a608bb55e8 25 namespace mbed {
jamesadevine 0:e1a608bb55e8 26
jamesadevine 0:e1a608bb55e8 27 /** A SPI slave, used for communicating with a SPI Master device
jamesadevine 0:e1a608bb55e8 28 *
jamesadevine 0:e1a608bb55e8 29 * The default format is set to 8-bits, mode 0, and a clock frequency of 1MHz
jamesadevine 0:e1a608bb55e8 30 *
jamesadevine 0:e1a608bb55e8 31 * Example:
jamesadevine 0:e1a608bb55e8 32 * @code
jamesadevine 0:e1a608bb55e8 33 * // Reply to a SPI master as slave
jamesadevine 0:e1a608bb55e8 34 *
jamesadevine 0:e1a608bb55e8 35 * #include "mbed.h"
jamesadevine 0:e1a608bb55e8 36 *
jamesadevine 0:e1a608bb55e8 37 * SPISlave device(p5, p6, p7, p8); // mosi, miso, sclk, ssel
jamesadevine 0:e1a608bb55e8 38 *
jamesadevine 0:e1a608bb55e8 39 * int main() {
jamesadevine 0:e1a608bb55e8 40 * device.reply(0x00); // Prime SPI with first reply
jamesadevine 0:e1a608bb55e8 41 * while(1) {
jamesadevine 0:e1a608bb55e8 42 * if(device.receive()) {
jamesadevine 0:e1a608bb55e8 43 * int v = device.read(); // Read byte from master
jamesadevine 0:e1a608bb55e8 44 * v = (v + 1) % 0x100; // Add one to it, modulo 256
jamesadevine 0:e1a608bb55e8 45 * device.reply(v); // Make this the next reply
jamesadevine 0:e1a608bb55e8 46 * }
jamesadevine 0:e1a608bb55e8 47 * }
jamesadevine 0:e1a608bb55e8 48 * }
jamesadevine 0:e1a608bb55e8 49 * @endcode
jamesadevine 0:e1a608bb55e8 50 */
jamesadevine 0:e1a608bb55e8 51 class SPISlave {
jamesadevine 0:e1a608bb55e8 52
jamesadevine 0:e1a608bb55e8 53 public:
jamesadevine 0:e1a608bb55e8 54
jamesadevine 0:e1a608bb55e8 55 /** Create a SPI slave connected to the specified pins
jamesadevine 0:e1a608bb55e8 56 *
jamesadevine 0:e1a608bb55e8 57 * mosi or miso can be specfied as NC if not used
jamesadevine 0:e1a608bb55e8 58 *
jamesadevine 0:e1a608bb55e8 59 * @param mosi SPI Master Out, Slave In pin
jamesadevine 0:e1a608bb55e8 60 * @param miso SPI Master In, Slave Out pin
jamesadevine 0:e1a608bb55e8 61 * @param sclk SPI Clock pin
jamesadevine 0:e1a608bb55e8 62 * @param ssel SPI chip select pin
jamesadevine 0:e1a608bb55e8 63 */
jamesadevine 0:e1a608bb55e8 64 SPISlave(PinName mosi, PinName miso, PinName sclk, PinName ssel);
jamesadevine 0:e1a608bb55e8 65
jamesadevine 0:e1a608bb55e8 66 /** Configure the data transmission format
jamesadevine 0:e1a608bb55e8 67 *
jamesadevine 0:e1a608bb55e8 68 * @param bits Number of bits per SPI frame (4 - 16)
jamesadevine 0:e1a608bb55e8 69 * @param mode Clock polarity and phase mode (0 - 3)
jamesadevine 0:e1a608bb55e8 70 *
jamesadevine 0:e1a608bb55e8 71 * @code
jamesadevine 0:e1a608bb55e8 72 * mode | POL PHA
jamesadevine 0:e1a608bb55e8 73 * -----+--------
jamesadevine 0:e1a608bb55e8 74 * 0 | 0 0
jamesadevine 0:e1a608bb55e8 75 * 1 | 0 1
jamesadevine 0:e1a608bb55e8 76 * 2 | 1 0
jamesadevine 0:e1a608bb55e8 77 * 3 | 1 1
jamesadevine 0:e1a608bb55e8 78 * @endcode
jamesadevine 0:e1a608bb55e8 79 */
jamesadevine 0:e1a608bb55e8 80 void format(int bits, int mode = 0);
jamesadevine 0:e1a608bb55e8 81
jamesadevine 0:e1a608bb55e8 82 /** Set the spi bus clock frequency
jamesadevine 0:e1a608bb55e8 83 *
jamesadevine 0:e1a608bb55e8 84 * @param hz SCLK frequency in hz (default = 1MHz)
jamesadevine 0:e1a608bb55e8 85 */
jamesadevine 0:e1a608bb55e8 86 void frequency(int hz = 1000000);
jamesadevine 0:e1a608bb55e8 87
jamesadevine 0:e1a608bb55e8 88 /** Polls the SPI to see if data has been received
jamesadevine 0:e1a608bb55e8 89 *
jamesadevine 0:e1a608bb55e8 90 * @returns
jamesadevine 0:e1a608bb55e8 91 * 0 if no data,
jamesadevine 0:e1a608bb55e8 92 * 1 otherwise
jamesadevine 0:e1a608bb55e8 93 */
jamesadevine 0:e1a608bb55e8 94 int receive(void);
jamesadevine 0:e1a608bb55e8 95
jamesadevine 0:e1a608bb55e8 96 /** Retrieve data from receive buffer as slave
jamesadevine 0:e1a608bb55e8 97 *
jamesadevine 0:e1a608bb55e8 98 * @returns
jamesadevine 0:e1a608bb55e8 99 * the data in the receive buffer
jamesadevine 0:e1a608bb55e8 100 */
jamesadevine 0:e1a608bb55e8 101 int read(void);
jamesadevine 0:e1a608bb55e8 102
jamesadevine 0:e1a608bb55e8 103 /** Fill the transmission buffer with the value to be written out
jamesadevine 0:e1a608bb55e8 104 * as slave on the next received message from the master.
jamesadevine 0:e1a608bb55e8 105 *
jamesadevine 0:e1a608bb55e8 106 * @param value the data to be transmitted next
jamesadevine 0:e1a608bb55e8 107 */
jamesadevine 0:e1a608bb55e8 108 void reply(int value);
jamesadevine 0:e1a608bb55e8 109
jamesadevine 0:e1a608bb55e8 110 protected:
jamesadevine 0:e1a608bb55e8 111 spi_t _spi;
jamesadevine 0:e1a608bb55e8 112
jamesadevine 0:e1a608bb55e8 113 int _bits;
jamesadevine 0:e1a608bb55e8 114 int _mode;
jamesadevine 0:e1a608bb55e8 115 int _hz;
jamesadevine 0:e1a608bb55e8 116 };
jamesadevine 0:e1a608bb55e8 117
jamesadevine 0:e1a608bb55e8 118 } // namespace mbed
jamesadevine 0:e1a608bb55e8 119
jamesadevine 0:e1a608bb55e8 120 #endif
jamesadevine 0:e1a608bb55e8 121
jamesadevine 0:e1a608bb55e8 122 #endif