mbed library
Fork of mbed by
I2C.h@43:e2ed12d17f06, 2012-10-26 (annotated)
- Committer:
- emilmont
- Date:
- Fri Oct 26 17:40:46 2012 +0100
- Revision:
- 43:e2ed12d17f06
- Parent:
- 27:7110ebee3484
- Child:
- 44:24d45a770a51
Update documentation
Who changed what in which revision?
User | Revision | Line number | New contents of line |
---|---|---|---|
simon.ford@mbed.co.uk | 0:82220227f4fa | 1 | /* mbed Microcontroller Library - I2C |
emilmont | 27:7110ebee3484 | 2 | * Copyright (c) 2007-2011 ARM Limited. All rights reserved. |
rolf.meyer@arm.com | 11:1c1ebd0324fa | 3 | */ |
simon.ford@mbed.co.uk | 0:82220227f4fa | 4 | |
simon.ford@mbed.co.uk | 0:82220227f4fa | 5 | #ifndef MBED_I2C_H |
simon.ford@mbed.co.uk | 0:82220227f4fa | 6 | #define MBED_I2C_H |
simon.ford@mbed.co.uk | 0:82220227f4fa | 7 | |
emilmont | 27:7110ebee3484 | 8 | #include "device.h" |
emilmont | 27:7110ebee3484 | 9 | |
emilmont | 27:7110ebee3484 | 10 | #if DEVICE_I2C |
emilmont | 27:7110ebee3484 | 11 | |
rolf.meyer@arm.com | 11:1c1ebd0324fa | 12 | #include "platform.h" |
rolf.meyer@arm.com | 11:1c1ebd0324fa | 13 | #include "PinNames.h" |
rolf.meyer@arm.com | 11:1c1ebd0324fa | 14 | #include "PeripheralNames.h" |
simon.ford@mbed.co.uk | 0:82220227f4fa | 15 | #include "Base.h" |
simon.ford@mbed.co.uk | 0:82220227f4fa | 16 | |
simon.ford@mbed.co.uk | 0:82220227f4fa | 17 | namespace mbed { |
simon.ford@mbed.co.uk | 0:82220227f4fa | 18 | |
emilmont | 43:e2ed12d17f06 | 19 | /** An I2C Master, used for communicating with I2C slave devices |
rolf.meyer@arm.com | 11:1c1ebd0324fa | 20 | * |
rolf.meyer@arm.com | 11:1c1ebd0324fa | 21 | * Example: |
emilmont | 43:e2ed12d17f06 | 22 | * @code |
emilmont | 43:e2ed12d17f06 | 23 | * // Read from I2C slave at address 0x62 |
emilmont | 43:e2ed12d17f06 | 24 | * |
emilmont | 43:e2ed12d17f06 | 25 | * #include "mbed.h" |
emilmont | 43:e2ed12d17f06 | 26 | * |
emilmont | 43:e2ed12d17f06 | 27 | * I2C i2c(p28, p27); |
emilmont | 43:e2ed12d17f06 | 28 | * |
emilmont | 43:e2ed12d17f06 | 29 | * int main() { |
emilmont | 43:e2ed12d17f06 | 30 | * int address = 0x62; |
emilmont | 43:e2ed12d17f06 | 31 | * char data[2]; |
emilmont | 43:e2ed12d17f06 | 32 | * i2c.read(address, data, 2); |
emilmont | 43:e2ed12d17f06 | 33 | * } |
emilmont | 43:e2ed12d17f06 | 34 | * @endcode |
simon.ford@mbed.co.uk | 0:82220227f4fa | 35 | */ |
simon.ford@mbed.co.uk | 0:82220227f4fa | 36 | class I2C : public Base { |
simon.ford@mbed.co.uk | 0:82220227f4fa | 37 | |
simon.ford@mbed.co.uk | 0:82220227f4fa | 38 | public: |
simon.ford@mbed.co.uk | 0:82220227f4fa | 39 | |
simon | 20:029aa53d7323 | 40 | enum RxStatus { |
simon | 20:029aa53d7323 | 41 | NoData |
simon | 20:029aa53d7323 | 42 | , MasterGeneralCall |
simon | 20:029aa53d7323 | 43 | , MasterWrite |
simon | 20:029aa53d7323 | 44 | , MasterRead |
simon | 20:029aa53d7323 | 45 | }; |
simon | 20:029aa53d7323 | 46 | |
simon | 21:3944f1e2fa4f | 47 | enum Acknowledge { |
simon | 21:3944f1e2fa4f | 48 | NoACK = 0 |
simon | 21:3944f1e2fa4f | 49 | , ACK = 1 |
simon | 21:3944f1e2fa4f | 50 | }; |
simon | 21:3944f1e2fa4f | 51 | |
emilmont | 43:e2ed12d17f06 | 52 | /** Create an I2C Master interface, connected to the specified pins |
rolf.meyer@arm.com | 11:1c1ebd0324fa | 53 | * |
emilmont | 43:e2ed12d17f06 | 54 | * @param sda I2C data line pin |
emilmont | 43:e2ed12d17f06 | 55 | * @param scl I2C clock line pin |
rolf.meyer@arm.com | 11:1c1ebd0324fa | 56 | */ |
rolf.meyer@arm.com | 11:1c1ebd0324fa | 57 | I2C(PinName sda, PinName scl, const char *name = NULL); |
simon.ford@mbed.co.uk | 0:82220227f4fa | 58 | |
emilmont | 43:e2ed12d17f06 | 59 | /** Set the frequency of the I2C interface |
rolf.meyer@arm.com | 11:1c1ebd0324fa | 60 | * |
emilmont | 43:e2ed12d17f06 | 61 | * @param 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 | |
emilmont | 43:e2ed12d17f06 | 65 | /** Read from an I2C slave |
simon.ford@mbed.co.uk | 0:82220227f4fa | 66 | * |
emilmont | 43:e2ed12d17f06 | 67 | * Performs a complete read transaction. The bottom bit of |
emilmont | 43:e2ed12d17f06 | 68 | * the address is forced to 1 to indicate a read. |
rolf.meyer@arm.com | 12:f63353af7be8 | 69 | * |
emilmont | 43:e2ed12d17f06 | 70 | * @param address 8-bit I2C slave address [ addr | 1 ] |
emilmont | 43:e2ed12d17f06 | 71 | * @param data Pointer to the byte-array to read data in to |
emilmont | 43:e2ed12d17f06 | 72 | * @param length Number of bytes to read |
emilmont | 43:e2ed12d17f06 | 73 | * @param repeated Repeated start, true - don't send stop at end |
emilmont | 43:e2ed12d17f06 | 74 | * |
emilmont | 43:e2ed12d17f06 | 75 | * @returns |
emilmont | 43:e2ed12d17f06 | 76 | * 0 on success (ack), |
emilmont | 43:e2ed12d17f06 | 77 | * non-0 on failure (nack) |
rolf.meyer@arm.com | 11:1c1ebd0324fa | 78 | */ |
simon | 20:029aa53d7323 | 79 | int read(int address, char *data, int length, bool repeated = false); |
simon.ford@mbed.co.uk | 0:82220227f4fa | 80 | |
emilmont | 43:e2ed12d17f06 | 81 | /** Read a single byte from the I2C bus |
simon | 21:3944f1e2fa4f | 82 | * |
emilmont | 43:e2ed12d17f06 | 83 | * @param ack indicates if the byte is to be acknowledged (1 = acknowledge) |
emilmont | 43:e2ed12d17f06 | 84 | * |
emilmont | 43:e2ed12d17f06 | 85 | * @returns |
emilmont | 43:e2ed12d17f06 | 86 | * the byte read |
simon | 21:3944f1e2fa4f | 87 | */ |
simon | 21:3944f1e2fa4f | 88 | int read(int ack); |
simon | 21:3944f1e2fa4f | 89 | |
emilmont | 43:e2ed12d17f06 | 90 | /** Write to an I2C slave |
rolf.meyer@arm.com | 11:1c1ebd0324fa | 91 | * |
emilmont | 43:e2ed12d17f06 | 92 | * Performs a complete write transaction. The bottom bit of |
emilmont | 43:e2ed12d17f06 | 93 | * the address is forced to 0 to indicate a write. |
rolf.meyer@arm.com | 12:f63353af7be8 | 94 | * |
emilmont | 43:e2ed12d17f06 | 95 | * @param address 8-bit I2C slave address [ addr | 0 ] |
emilmont | 43:e2ed12d17f06 | 96 | * @param data Pointer to the byte-array data to send |
emilmont | 43:e2ed12d17f06 | 97 | * @param length Number of bytes to send |
emilmont | 43:e2ed12d17f06 | 98 | * @param repeated Repeated start, true - do not send stop at end |
emilmont | 43:e2ed12d17f06 | 99 | * |
emilmont | 43:e2ed12d17f06 | 100 | * @returns |
emilmont | 43:e2ed12d17f06 | 101 | * 0 on success (ack), |
emilmont | 43:e2ed12d17f06 | 102 | * non-0 on failure (nack) |
rolf.meyer@arm.com | 11:1c1ebd0324fa | 103 | */ |
simon | 20:029aa53d7323 | 104 | int write(int address, const char *data, int length, bool repeated = false); |
simon | 21:3944f1e2fa4f | 105 | |
emilmont | 43:e2ed12d17f06 | 106 | /** Write single byte out on the I2C bus |
emilmont | 43:e2ed12d17f06 | 107 | * |
emilmont | 43:e2ed12d17f06 | 108 | * @param data data to write out on bus |
simon | 21:3944f1e2fa4f | 109 | * |
emilmont | 43:e2ed12d17f06 | 110 | * @returns |
emilmont | 43:e2ed12d17f06 | 111 | * '1' if an ACK was received, |
emilmont | 43:e2ed12d17f06 | 112 | * '0' otherwise |
simon | 21:3944f1e2fa4f | 113 | */ |
simon | 21:3944f1e2fa4f | 114 | int write(int data); |
simon | 21:3944f1e2fa4f | 115 | |
emilmont | 43:e2ed12d17f06 | 116 | /** Creates a start condition on the I2C bus |
simon | 21:3944f1e2fa4f | 117 | */ |
simon | 21:3944f1e2fa4f | 118 | void start(void); |
simon | 21:3944f1e2fa4f | 119 | |
emilmont | 43:e2ed12d17f06 | 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 |
emilmont | 27:7110ebee3484 | 137 | |
emilmont | 27:7110ebee3484 | 138 | #endif |
emilmont | 27:7110ebee3484 | 139 |