Takayuki Ito / mbed

Library

Dependents:   OSCTest_2

Fork of mbed by gokmen ascioglu

SPIHalfDuplex.h@0:a8fa94490a0a, 2012-09-22 (annotated)

Committer:
gokmenascioglu
Date:
Sat Sep 22 10:32:07 2012 +0000
Revision:
0:a8fa94490a0a
alican library

Who changed what in which revision?

UserRevisionLine numberNew contents of line
gokmenascioglu 0:a8fa94490a0a 1 /* mbed Microcontroller Library - SPIHalfDuplex
gokmenascioglu 0:a8fa94490a0a 2 * Copyright (c) 2010-2011 ARM Limited. All rights reserved.
gokmenascioglu 0:a8fa94490a0a 3 */
gokmenascioglu 0:a8fa94490a0a 4
gokmenascioglu 0:a8fa94490a0a 5 #ifndef MBED_SPIHALFDUPLEX_H
gokmenascioglu 0:a8fa94490a0a 6 #define MBED_SPIHALFDUPLEX_H
gokmenascioglu 0:a8fa94490a0a 7
gokmenascioglu 0:a8fa94490a0a 8 #include "device.h"
gokmenascioglu 0:a8fa94490a0a 9
gokmenascioglu 0:a8fa94490a0a 10 #if DEVICE_SPI
gokmenascioglu 0:a8fa94490a0a 11
gokmenascioglu 0:a8fa94490a0a 12 #include "SPI.h"
gokmenascioglu 0:a8fa94490a0a 13
gokmenascioglu 0:a8fa94490a0a 14 namespace mbed {
gokmenascioglu 0:a8fa94490a0a 15
gokmenascioglu 0:a8fa94490a0a 16 /* Class: SPIHalfDuplex
gokmenascioglu 0:a8fa94490a0a 17 * A SPI half-duplex master, used for communicating with SPI slave devices
gokmenascioglu 0:a8fa94490a0a 18 * over a shared data line.
gokmenascioglu 0:a8fa94490a0a 19 *
gokmenascioglu 0:a8fa94490a0a 20 * The default format is set to 8-bits for both master and slave, and a
gokmenascioglu 0:a8fa94490a0a 21 * clock frequency of 1MHz
gokmenascioglu 0:a8fa94490a0a 22 *
gokmenascioglu 0:a8fa94490a0a 23 * Most SPI devies will also require Chip Select and Reset signals. These
gokmenascioglu 0:a8fa94490a0a 24 * can be controlled using <DigitalOut> pins.
gokmenascioglu 0:a8fa94490a0a 25 *
gokmenascioglu 0:a8fa94490a0a 26 * Although this is for a shared data line, both MISO and MOSI are defined,
gokmenascioglu 0:a8fa94490a0a 27 * and should be tied together externally to the mbed. This class handles
gokmenascioglu 0:a8fa94490a0a 28 * the tri-stating of the MOSI pin.
gokmenascioglu 0:a8fa94490a0a 29 *
gokmenascioglu 0:a8fa94490a0a 30 * Example:
gokmenascioglu 0:a8fa94490a0a 31 * > // Send a byte to a SPI half-duplex slave, and record the response
gokmenascioglu 0:a8fa94490a0a 32 * >
gokmenascioglu 0:a8fa94490a0a 33 * > #include "mbed.h"
gokmenascioglu 0:a8fa94490a0a 34 * >
gokmenascioglu 0:a8fa94490a0a 35 * > SPIHalfDuplex device(p5, p6, p7) // mosi, miso, sclk
gokmenascioglu 0:a8fa94490a0a 36 * >
gokmenascioglu 0:a8fa94490a0a 37 * > int main() {
gokmenascioglu 0:a8fa94490a0a 38 * > int respone = device.write(0xAA);
gokmenascioglu 0:a8fa94490a0a 39 * > }
gokmenascioglu 0:a8fa94490a0a 40 */
gokmenascioglu 0:a8fa94490a0a 41
gokmenascioglu 0:a8fa94490a0a 42 class SPIHalfDuplex : public SPI {
gokmenascioglu 0:a8fa94490a0a 43
gokmenascioglu 0:a8fa94490a0a 44 public:
gokmenascioglu 0:a8fa94490a0a 45
gokmenascioglu 0:a8fa94490a0a 46 /* Constructor: SPIHalfDuplex
gokmenascioglu 0:a8fa94490a0a 47 * Create a SPI half-duplex master connected to the specified pins
gokmenascioglu 0:a8fa94490a0a 48 *
gokmenascioglu 0:a8fa94490a0a 49 * Variables:
gokmenascioglu 0:a8fa94490a0a 50 * mosi - SPI Master Out, Slave In pin
gokmenascioglu 0:a8fa94490a0a 51 * miso - SPI Master In, Slave Out pin
gokmenascioglu 0:a8fa94490a0a 52 * sclk - SPI Clock pin
gokmenascioglu 0:a8fa94490a0a 53 * name - (optional) A string to identify the object
gokmenascioglu 0:a8fa94490a0a 54 *
gokmenascioglu 0:a8fa94490a0a 55 * Pin Options:
gokmenascioglu 0:a8fa94490a0a 56 * (5, 6, 7) or (11, 12, 13)
gokmenascioglu 0:a8fa94490a0a 57 *
gokmenascioglu 0:a8fa94490a0a 58 * mosi or miso can be specfied as NC if not used
gokmenascioglu 0:a8fa94490a0a 59 */
gokmenascioglu 0:a8fa94490a0a 60 SPIHalfDuplex(PinName mosi, PinName miso, PinName sclk,
gokmenascioglu 0:a8fa94490a0a 61 const char *name = NULL);
gokmenascioglu 0:a8fa94490a0a 62
gokmenascioglu 0:a8fa94490a0a 63 #if 0 // Inherited from SPI - documentation only
gokmenascioglu 0:a8fa94490a0a 64 /* Function: format
gokmenascioglu 0:a8fa94490a0a 65 * Configure the data transmission format
gokmenascioglu 0:a8fa94490a0a 66 *
gokmenascioglu 0:a8fa94490a0a 67 * Variables:
gokmenascioglu 0:a8fa94490a0a 68 * bits - Number of bits per SPI frame (4 - 16)
gokmenascioglu 0:a8fa94490a0a 69 * mode - Clock polarity and phase mode (0 - 3)
gokmenascioglu 0:a8fa94490a0a 70 *
gokmenascioglu 0:a8fa94490a0a 71 * > mode | POL PHA
gokmenascioglu 0:a8fa94490a0a 72 * > -----+--------
gokmenascioglu 0:a8fa94490a0a 73 * > 0 | 0 0
gokmenascioglu 0:a8fa94490a0a 74 * > 1 | 0 1
gokmenascioglu 0:a8fa94490a0a 75 * > 2 | 1 0
gokmenascioglu 0:a8fa94490a0a 76 * > 3 | 1 1
gokmenascioglu 0:a8fa94490a0a 77 */
gokmenascioglu 0:a8fa94490a0a 78 void format(int bits, int mode = 0);
gokmenascioglu 0:a8fa94490a0a 79
gokmenascioglu 0:a8fa94490a0a 80 /* Function: frequency
gokmenascioglu 0:a8fa94490a0a 81 * Set the spi bus clock frequency
gokmenascioglu 0:a8fa94490a0a 82 *
gokmenascioglu 0:a8fa94490a0a 83 * Variables:
gokmenascioglu 0:a8fa94490a0a 84 * hz - SCLK frequency in hz (default = 1MHz)
gokmenascioglu 0:a8fa94490a0a 85 */
gokmenascioglu 0:a8fa94490a0a 86 void frequency(int hz = 1000000);
gokmenascioglu 0:a8fa94490a0a 87 #endif
gokmenascioglu 0:a8fa94490a0a 88
gokmenascioglu 0:a8fa94490a0a 89 /* Function: write
gokmenascioglu 0:a8fa94490a0a 90 * Write to the SPI Slave and return the response
gokmenascioglu 0:a8fa94490a0a 91 *
gokmenascioglu 0:a8fa94490a0a 92 * Variables:
gokmenascioglu 0:a8fa94490a0a 93 * value - Data to be sent to the SPI slave
gokmenascioglu 0:a8fa94490a0a 94 * returns - Response from the SPI slave
gokmenascioglu 0:a8fa94490a0a 95 */
gokmenascioglu 0:a8fa94490a0a 96 virtual int write(int value);
gokmenascioglu 0:a8fa94490a0a 97
gokmenascioglu 0:a8fa94490a0a 98 /* Function: slave_format
gokmenascioglu 0:a8fa94490a0a 99 * Set the number of databits expected from the slave, from 4-16
gokmenascioglu 0:a8fa94490a0a 100 *
gokmenascioglu 0:a8fa94490a0a 101 * Variables:
gokmenascioglu 0:a8fa94490a0a 102 * sbits - Number of expected bits in the slave response
gokmenascioglu 0:a8fa94490a0a 103 */
gokmenascioglu 0:a8fa94490a0a 104 void slave_format(int sbits);
gokmenascioglu 0:a8fa94490a0a 105
gokmenascioglu 0:a8fa94490a0a 106 protected:
gokmenascioglu 0:a8fa94490a0a 107 PinName _mosi;
gokmenascioglu 0:a8fa94490a0a 108 PinName _miso;
gokmenascioglu 0:a8fa94490a0a 109 int _sbits;
gokmenascioglu 0:a8fa94490a0a 110
gokmenascioglu 0:a8fa94490a0a 111 }; // End of class
gokmenascioglu 0:a8fa94490a0a 112
gokmenascioglu 0:a8fa94490a0a 113 } // End of namespace mbed
gokmenascioglu 0:a8fa94490a0a 114
gokmenascioglu 0:a8fa94490a0a 115 #endif
gokmenascioglu 0:a8fa94490a0a 116
gokmenascioglu 0:a8fa94490a0a 117 #endif