Matthew Sims / mbed

Lab 1 Program C

Dependents:   Lab1C

Fork of mbed by -deleted-

I2C.h@21:3944f1e2fa4f, 2010-06-17 (annotated)

Committer:
simon
Date:
Thu Jun 17 16:23:14 2010 +0000
Revision:
21:3944f1e2fa4f
Parent:
20:029aa53d7323
Child:
22:9114680c05da
* CAN fixes

 * Serial Interrupt

 * I2C low level routines

Who changed what in which revision?

UserRevisionLine numberNew contents of line
simon.ford@mbed.co.uk 0:82220227f4fa 1 /* mbed Microcontroller Library - I2C
rolf.meyer@arm.com 11:1c1ebd0324fa 2 * Copyright (c) 2007-2009 ARM Limited. All rights reserved.
rolf.meyer@arm.com 11:1c1ebd0324fa 3 * sford
rolf.meyer@arm.com 11:1c1ebd0324fa 4 */
simon.ford@mbed.co.uk 0:82220227f4fa 5
simon.ford@mbed.co.uk 0:82220227f4fa 6 #ifndef MBED_I2C_H
simon.ford@mbed.co.uk 0:82220227f4fa 7 #define MBED_I2C_H
simon.ford@mbed.co.uk 0:82220227f4fa 8
rolf.meyer@arm.com 11:1c1ebd0324fa 9 #include "platform.h"
rolf.meyer@arm.com 11:1c1ebd0324fa 10 #include "PinNames.h"
rolf.meyer@arm.com 11:1c1ebd0324fa 11 #include "PeripheralNames.h"
simon.ford@mbed.co.uk 0:82220227f4fa 12 #include "Base.h"
simon.ford@mbed.co.uk 0:82220227f4fa 13
simon.ford@mbed.co.uk 0:82220227f4fa 14 namespace mbed {
simon.ford@mbed.co.uk 0:82220227f4fa 15
simon.ford@mbed.co.uk 0:82220227f4fa 16 /* Class: I2C
simon.ford@mbed.co.uk 0:82220227f4fa 17 * An I2C Master, used for communicating with I2C slave devices
rolf.meyer@arm.com 11:1c1ebd0324fa 18 *
rolf.meyer@arm.com 11:1c1ebd0324fa 19 * Example:
simon 20:029aa53d7323 20 * > // Read from I2C slave at address 0x62
rolf.meyer@arm.com 11:1c1ebd0324fa 21 * >
rolf.meyer@arm.com 11:1c1ebd0324fa 22 * > #include "mbed.h"
rolf.meyer@arm.com 11:1c1ebd0324fa 23 * >
rolf.meyer@arm.com 11:1c1ebd0324fa 24 * > I2C i2c(p28, p27);
rolf.meyer@arm.com 11:1c1ebd0324fa 25 * >
rolf.meyer@arm.com 11:1c1ebd0324fa 26 * > int main() {
rolf.meyer@arm.com 12:f63353af7be8 27 * > int address = 0x62;
rolf.meyer@arm.com 11:1c1ebd0324fa 28 * > char data[2];
rolf.meyer@arm.com 12:f63353af7be8 29 * > i2c.read(address, data, 2);
rolf.meyer@arm.com 11:1c1ebd0324fa 30 * > }
simon.ford@mbed.co.uk 0:82220227f4fa 31 */
simon.ford@mbed.co.uk 0:82220227f4fa 32 class I2C : public Base {
simon.ford@mbed.co.uk 0:82220227f4fa 33
simon.ford@mbed.co.uk 0:82220227f4fa 34 public:
simon.ford@mbed.co.uk 0:82220227f4fa 35
simon 20:029aa53d7323 36 enum RxStatus {
simon 20:029aa53d7323 37 NoData
simon 20:029aa53d7323 38 , MasterGeneralCall
simon 20:029aa53d7323 39 , MasterWrite
simon 20:029aa53d7323 40 , MasterRead
simon 20:029aa53d7323 41 };
simon 20:029aa53d7323 42
simon 21:3944f1e2fa4f 43 enum Acknowledge {
simon 21:3944f1e2fa4f 44 NoACK = 0
simon 21:3944f1e2fa4f 45 , ACK = 1
simon 21:3944f1e2fa4f 46 };
simon 21:3944f1e2fa4f 47
rolf.meyer@arm.com 11:1c1ebd0324fa 48 /* Constructor: I2C
rolf.meyer@arm.com 11:1c1ebd0324fa 49 * Create an I2C Master interface, connected to the specified pins
rolf.meyer@arm.com 11:1c1ebd0324fa 50 *
rolf.meyer@arm.com 11:1c1ebd0324fa 51 * Variables:
rolf.meyer@arm.com 11:1c1ebd0324fa 52 * sda - I2C data line pin
rolf.meyer@arm.com 11:1c1ebd0324fa 53 * scl - I2C clock line pin
rolf.meyer@arm.com 11:1c1ebd0324fa 54 */
rolf.meyer@arm.com 11:1c1ebd0324fa 55 I2C(PinName sda, PinName scl, const char *name = NULL);
simon.ford@mbed.co.uk 0:82220227f4fa 56
rolf.meyer@arm.com 11:1c1ebd0324fa 57 /* Function: frequency
rolf.meyer@arm.com 11:1c1ebd0324fa 58 * Set the frequency of the I2C interface
rolf.meyer@arm.com 11:1c1ebd0324fa 59 *
rolf.meyer@arm.com 11:1c1ebd0324fa 60 * Variables:
rolf.meyer@arm.com 11:1c1ebd0324fa 61 * hz - The bus frequency in hertz
rolf.meyer@arm.com 11:1c1ebd0324fa 62 */
rolf.meyer@arm.com 11:1c1ebd0324fa 63 void frequency(int hz);
rolf.meyer@arm.com 11:1c1ebd0324fa 64
rolf.meyer@arm.com 11:1c1ebd0324fa 65 /* Function: read
rolf.meyer@arm.com 11:1c1ebd0324fa 66 * Read from an I2C slave
simon.ford@mbed.co.uk 0:82220227f4fa 67 *
rolf.meyer@arm.com 12:f63353af7be8 68 * Performs a complete read transaction. The bottom bit of
rolf.meyer@arm.com 12:f63353af7be8 69 * the address is forced to 1 to indicate a read.
rolf.meyer@arm.com 12:f63353af7be8 70 *
rolf.meyer@arm.com 11:1c1ebd0324fa 71 * Variables:
rolf.meyer@arm.com 12:f63353af7be8 72 * address - 8-bit I2C slave address [ addr | 1 ]
rolf.meyer@arm.com 11:1c1ebd0324fa 73 * data - Pointer to the byte-array to read data in to
rolf.meyer@arm.com 11:1c1ebd0324fa 74 * length - Number of bytes to read
simon 20:029aa53d7323 75 * repeated - Repeated start, true - don't send stop at end
rolf.meyer@arm.com 12:f63353af7be8 76 * returns - 0 on success (ack), or non-0 on failure (nack)
rolf.meyer@arm.com 11:1c1ebd0324fa 77 */
simon 20:029aa53d7323 78 int read(int address, char *data, int length, bool repeated = false);
simon.ford@mbed.co.uk 0:82220227f4fa 79
simon 21:3944f1e2fa4f 80 /* Function: read
simon 21:3944f1e2fa4f 81 * Read a single byte from the I2C bus
simon 21:3944f1e2fa4f 82 *
simon 21:3944f1e2fa4f 83 * Variables:
simon 21:3944f1e2fa4f 84 * ack - indicates if the byte is to be acknowledged (1 = acknowledge)
simon 21:3944f1e2fa4f 85 * returns - the byte read
simon 21:3944f1e2fa4f 86 */
simon 21:3944f1e2fa4f 87 int read(int ack);
simon 21:3944f1e2fa4f 88
rolf.meyer@arm.com 11:1c1ebd0324fa 89 /* Function: write
rolf.meyer@arm.com 11:1c1ebd0324fa 90 * Write to an I2C slave
rolf.meyer@arm.com 11:1c1ebd0324fa 91 *
rolf.meyer@arm.com 12:f63353af7be8 92 * Performs a complete write transaction. The bottom bit of
rolf.meyer@arm.com 12:f63353af7be8 93 * the address is forced to 0 to indicate a write.
rolf.meyer@arm.com 12:f63353af7be8 94 *
rolf.meyer@arm.com 11:1c1ebd0324fa 95 * Variables:
rolf.meyer@arm.com 12:f63353af7be8 96 * address - 8-bit I2C slave address [ addr | 0 ]
rolf.meyer@arm.com 11:1c1ebd0324fa 97 * data - Pointer to the byte-array data to send
rolf.meyer@arm.com 11:1c1ebd0324fa 98 * length - Number of bytes to send
simon 20:029aa53d7323 99 * repeated - Repeated start, true - do not send stop at end
rolf.meyer@arm.com 12:f63353af7be8 100 * returns - 0 on success (ack), or non-0 on failure (nack)
rolf.meyer@arm.com 11:1c1ebd0324fa 101 */
simon 20:029aa53d7323 102 int write(int address, const char *data, int length, bool repeated = false);
simon 21:3944f1e2fa4f 103
simon 21:3944f1e2fa4f 104 /* Function: write
simon 21:3944f1e2fa4f 105 * Write single byte out on the I2C bus
simon 21:3944f1e2fa4f 106 *
simon 21:3944f1e2fa4f 107 * Variables:
simon 21:3944f1e2fa4f 108 * data - data to write out on bus
simon 21:3944f1e2fa4f 109 * returns - a '1' if an ACK was retrieved, a '0' otherwise
simon 21:3944f1e2fa4f 110 */
simon 21:3944f1e2fa4f 111 int write(int data);
simon 21:3944f1e2fa4f 112
simon 21:3944f1e2fa4f 113 /* Function: start
simon 21:3944f1e2fa4f 114 * Creates a start condition on the I2C bus
simon 21:3944f1e2fa4f 115 */
simon 21:3944f1e2fa4f 116
simon 21:3944f1e2fa4f 117 void start(void);
simon 21:3944f1e2fa4f 118
simon 21:3944f1e2fa4f 119 /* Function: stop
simon 21:3944f1e2fa4f 120 * Creates a stop condition on the I2C bus
simon 21:3944f1e2fa4f 121 */
simon 21:3944f1e2fa4f 122 void stop(void);
simon 21:3944f1e2fa4f 123
simon.ford@mbed.co.uk 0:82220227f4fa 124 protected:
simon.ford@mbed.co.uk 0:82220227f4fa 125
rolf.meyer@arm.com 11:1c1ebd0324fa 126 void aquire();
simon 20:029aa53d7323 127
simon 20:029aa53d7323 128 I2CName _i2c;
simon 20:029aa53d7323 129 static I2C *_owner;
simon 20:029aa53d7323 130 int _hz;
simon.ford@mbed.co.uk 0:82220227f4fa 131
simon.ford@mbed.co.uk 0:82220227f4fa 132 };
simon.ford@mbed.co.uk 0:82220227f4fa 133
rolf.meyer@arm.com 11:1c1ebd0324fa 134 } // namespace mbed
simon.ford@mbed.co.uk 0:82220227f4fa 135
simon.ford@mbed.co.uk 1:6b7f447ca868 136 #endif