1 /*------------------------------------------------------------------------- 2 i2c.h - I2C communications module library header 3 4 Copyright (C) 2005, Vangelis Rokas <vrokas AT otenet.gr> 5 6 This library is free software; you can redistribute it and/or modify it 7 under the terms of the GNU General Public License as published by the 8 Free Software Foundation; either version 2, or (at your option) any 9 later version. 10 11 This library is distributed in the hope that it will be useful, 12 but WITHOUT ANY WARRANTY; without even the implied warranty of 13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 GNU General Public License for more details. 15 16 You should have received a copy of the GNU General Public License 17 along with this library; see the file COPYING. If not, write to the 18 Free Software Foundation, 51 Franklin Street, Fifth Floor, Boston, 19 MA 02110-1301, USA. 20 21 As a special exception, if you link this library with other files, 22 some of which are compiled with SDCC, to produce an executable, 23 this library does not by itself cause the resulting executable to 24 be covered by the GNU General Public License. This exception does 25 not however invalidate any other reasons why the executable file 26 might be covered by the GNU General Public License. 27 -------------------------------------------------------------------------*/ 28 /* 29 * Devices implemented: 30 * PIC18F[24][45][28] 31 */ 32 33 #ifndef __I2C_H__ 34 #define __I2C_H__ 35 36 /* link the I/O library */ 37 #pragma library io 38 39 #include <pic18fregs.h> 40 41 42 #define _I2CPARAM_SPEC __data 43 44 45 /* I2C modes of operation */ 46 #define I2C_SLAVE10B_INT 0x0f 47 #define I2C_SLAVE7B_INT 0x0e 48 #define I2C_SLAVE_IDLE 0x0b 49 #define I2C_MASTER 0x08 50 #define I2C_SLAVE10B 0x07 51 #define I2C_SLAVE7B 0x06 52 53 54 /* slew rate control */ 55 #define I2C_SLEW_OFF 0x80 56 #define I2C_SLEW_ON 0x00 57 58 /* macros to generate hardware conditions on I2C module */ 59 60 /* generate stop condition */ 61 #define I2C_STOP() do { SSPCON2bits.PEN = 1; } while (0) 62 63 /* generate start condition */ 64 #define I2C_START() do { SSPCON2bits.SEN = 1; } while (0) 65 66 /* generate restart condition */ 67 #define I2C_RESTART() do { SSPCON2bits.RSEN = 1; } while (0) 68 69 /* generate not acknowledge condition */ 70 #define I2C_NACK() do { SSPCON2bits.ACKDT = 1; SSPCON2bits.ACKEN = 1; } while (0) 71 72 /* generate acknowledge condition */ 73 #define I2C_ACK() do { SSPCON2bits.ACKDT = 0; SSPCON2bits.ACKEN = 1; } while (0) 74 75 /* wait until I2C is idle */ 76 #define I2C_IDLE() do { /* busy waiting */ } while ((SSPCON2 & 0x1f) | (SSPSTATbits.R_W)) 77 78 /* is data ready from I2C module ?? */ 79 #define I2C_DRDY() (SSPSTATbits.BF) 80 81 82 /* function equivalent to macros for generating hardware conditions */ 83 84 /* stop */ 85 void i2c_stop(void); 86 87 /* start */ 88 void i2c_start(void); 89 90 /* restart */ 91 void i2c_restart(void); 92 93 /* not acknowledge */ 94 void i2c_nack(void); 95 96 /* acknowledge */ 97 void i2c_ack(void); 98 99 /* wait until I2C goes idle */ 100 void i2c_idle(void); 101 102 /* is character ready in I2C buffer ?? */ 103 unsigned char i2c_drdy(void); 104 105 /* read a character from I2C module */ 106 unsigned char i2c_readchar(void); 107 108 /* read a string from I2C module */ 109 char i2c_readstr(_I2CPARAM_SPEC unsigned char *ptr, unsigned char len); 110 111 /* write a character to I2C module */ 112 char i2c_writechar(unsigned char dat); 113 114 /* write a string to I2C module */ 115 char i2c_writestr(unsigned char *ptr); 116 117 /* configure I2C port for operation */ 118 void i2c_open(unsigned char mode, unsigned char slew, unsigned char addr_brd); 119 120 void i2c_close(void); 121 122 #endif /* __I2C_H__ */ 123