I2CR - A hacked library to offer I2C functionality simil…

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A hacked library to offer I2C functionality similar to the standard mbed library for I2C1 only. Is seemingly required when using the v29 beta mbed library as of 12.05.2011, as the I2C does not seem to work otherwise. Has been developed and tested with the ADXL345 accelerometer.

Dependents: SensorsThingSpeak

I2CR.cpp@0:375ecd0ed73d, 2011-05-12 (annotated)

Committer:: ShockSoc
Date:: Thu May 12 09:24:27 2011 +0000
Revision:: 0:375ecd0ed73d

Who changed what in which revision?

User	Revision	Line number	New contents of line
ShockSoc	0:375ecd0ed73d	1	#include "I2CR.h"
ShockSoc	0:375ecd0ed73d	2
ShockSoc	0:375ecd0ed73d	3	//Constructor
ShockSoc	0:375ecd0ed73d	4	I2CR::I2CR() {
ShockSoc	0:375ecd0ed73d	5
ShockSoc	0:375ecd0ed73d	6	//set pins to i2c1
ShockSoc	0:375ecd0ed73d	7	LPC_PINCON->PINSEL0 = LPC_PINCON->PINSEL0 \| 0xF;
ShockSoc	0:375ecd0ed73d	8	//set to no pull up/down resistors
ShockSoc	0:375ecd0ed73d	9	LPC_PINCON->PINMODE0 = LPC_PINCON->PINMODE0 \| 0xA;
ShockSoc	0:375ecd0ed73d	10	//set to open drain mode
ShockSoc	0:375ecd0ed73d	11	LPC_PINCON->PINMODE_OD0 = LPC_PINCON->PINMODE_OD0 \| 0x3;
ShockSoc	0:375ecd0ed73d	12
ShockSoc	0:375ecd0ed73d	13	//turn on power
ShockSoc	0:375ecd0ed73d	14	LPC_SC->PCONP = LPC_SC->PCONP \| 0x00080000;
ShockSoc	0:375ecd0ed73d	15
ShockSoc	0:375ecd0ed73d	16	//set clock to 100kHz
ShockSoc	0:375ecd0ed73d	17	LPC_I2C1->I2SCLL = 120;
ShockSoc	0:375ecd0ed73d	18	LPC_I2C1->I2SCLH = 120;
ShockSoc	0:375ecd0ed73d	19
ShockSoc	0:375ecd0ed73d	20	//enable i2c1 i2en
ShockSoc	0:375ecd0ed73d	21	LPC_I2C1->I2CONSET = 0x40;
ShockSoc	0:375ecd0ed73d	22	//clear sta si and aa
ShockSoc	0:375ecd0ed73d	23	LPC_I2C1->I2CONCLR = 0x2C;
ShockSoc	0:375ecd0ed73d	24
ShockSoc	0:375ecd0ed73d	25
ShockSoc	0:375ecd0ed73d	26	}
ShockSoc	0:375ecd0ed73d	27
ShockSoc	0:375ecd0ed73d	28	//Write function
ShockSoc	0:375ecd0ed73d	29	int I2CR::write(int address, const char* data, int length) {
ShockSoc	0:375ecd0ed73d	30	//MASTER TRANSMITTER
ShockSoc	0:375ecd0ed73d	31
ShockSoc	0:375ecd0ed73d	32	//send start condition
ShockSoc	0:375ecd0ed73d	33	LPC_I2C1->I2CONSET = 0x20;
ShockSoc	0:375ecd0ed73d	34
ShockSoc	0:375ecd0ed73d	35	//block until interrupt
ShockSoc	0:375ecd0ed73d	36	while ((LPC_I2C1->I2CONSET & 0x8) != 0x8) {}
ShockSoc	0:375ecd0ed73d	37
ShockSoc	0:375ecd0ed73d	38	//i2stat should be 0x08. could check
ShockSoc	0:375ecd0ed73d	39	if (LPC_I2C1->I2STAT != 0x08) {
ShockSoc	0:375ecd0ed73d	40	printf("START %x\r\n",LPC_I2C1->I2STAT);
ShockSoc	0:375ecd0ed73d	41	//stop if failed
ShockSoc	0:375ecd0ed73d	42	LPC_I2C1->I2CONSET = 0x10;
ShockSoc	0:375ecd0ed73d	43	return -1;
ShockSoc	0:375ecd0ed73d	44	}
ShockSoc	0:375ecd0ed73d	45
ShockSoc	0:375ecd0ed73d	46	//clear start condition
ShockSoc	0:375ecd0ed73d	47	LPC_I2C1->I2CONCLR = 0x20;
ShockSoc	0:375ecd0ed73d	48
ShockSoc	0:375ecd0ed73d	49	//load i2dat
ShockSoc	0:375ecd0ed73d	50	LPC_I2C1->I2DAT = address;
ShockSoc	0:375ecd0ed73d	51
ShockSoc	0:375ecd0ed73d	52	//reset si
ShockSoc	0:375ecd0ed73d	53	LPC_I2C1->I2CONCLR = 0x08;
ShockSoc	0:375ecd0ed73d	54
ShockSoc	0:375ecd0ed73d	55	//block until interrupt
ShockSoc	0:375ecd0ed73d	56	while ((LPC_I2C1->I2CONSET & 0x8) != 0x8) {}
ShockSoc	0:375ecd0ed73d	57
ShockSoc	0:375ecd0ed73d	58	//i2stat should be ack received
ShockSoc	0:375ecd0ed73d	59	if (LPC_I2C1->I2STAT != 0x18) {
ShockSoc	0:375ecd0ed73d	60	printf("ADD %x\r\n",LPC_I2C1->I2STAT);
ShockSoc	0:375ecd0ed73d	61	//stop
ShockSoc	0:375ecd0ed73d	62	LPC_I2C1->I2CONSET = 0x10;
ShockSoc	0:375ecd0ed73d	63	return -1;
ShockSoc	0:375ecd0ed73d	64	}
ShockSoc	0:375ecd0ed73d	65
ShockSoc	0:375ecd0ed73d	66	for (int i=0; i<length; i++) {
ShockSoc	0:375ecd0ed73d	67
ShockSoc	0:375ecd0ed73d	68	//load i2dat
ShockSoc	0:375ecd0ed73d	69	LPC_I2C1->I2DAT = data[i];
ShockSoc	0:375ecd0ed73d	70
ShockSoc	0:375ecd0ed73d	71	//reset si
ShockSoc	0:375ecd0ed73d	72	LPC_I2C1->I2CONCLR = 0x08;
ShockSoc	0:375ecd0ed73d	73
ShockSoc	0:375ecd0ed73d	74	//block until interrupt
ShockSoc	0:375ecd0ed73d	75	while ((LPC_I2C1->I2CONSET & 0x8) != 0x8) {}
ShockSoc	0:375ecd0ed73d	76
ShockSoc	0:375ecd0ed73d	77	//i2stat should be ack received
ShockSoc	0:375ecd0ed73d	78	if (LPC_I2C1->I2STAT != 0x28) {
ShockSoc	0:375ecd0ed73d	79	printf("DATA%d %x\r\n",i,LPC_I2C1->I2STAT);
ShockSoc	0:375ecd0ed73d	80	//stop
ShockSoc	0:375ecd0ed73d	81	LPC_I2C1->I2CONSET = 0x10;
ShockSoc	0:375ecd0ed73d	82	return -1;
ShockSoc	0:375ecd0ed73d	83	}
ShockSoc	0:375ecd0ed73d	84	}
ShockSoc	0:375ecd0ed73d	85
ShockSoc	0:375ecd0ed73d	86	//stop
ShockSoc	0:375ecd0ed73d	87	LPC_I2C1->I2CONSET = 0x10;
ShockSoc	0:375ecd0ed73d	88
ShockSoc	0:375ecd0ed73d	89	//reset si
ShockSoc	0:375ecd0ed73d	90	LPC_I2C1->I2CONCLR = 0x08;
ShockSoc	0:375ecd0ed73d	91
ShockSoc	0:375ecd0ed73d	92	return 0;
ShockSoc	0:375ecd0ed73d	93	}
ShockSoc	0:375ecd0ed73d	94
ShockSoc	0:375ecd0ed73d	95
ShockSoc	0:375ecd0ed73d	96	int I2CR::read(int address, char* data, int length) {
ShockSoc	0:375ecd0ed73d	97
ShockSoc	0:375ecd0ed73d	98	//MASTER RECEIVER
ShockSoc	0:375ecd0ed73d	99
ShockSoc	0:375ecd0ed73d	100	//send start condition
ShockSoc	0:375ecd0ed73d	101	LPC_I2C1->I2CONSET = 0x20;
ShockSoc	0:375ecd0ed73d	102
ShockSoc	0:375ecd0ed73d	103	//block until interrupt
ShockSoc	0:375ecd0ed73d	104	while ((LPC_I2C1->I2CONSET & 0x8) != 0x8) {}
ShockSoc	0:375ecd0ed73d	105
ShockSoc	0:375ecd0ed73d	106	//i2stat should be 0x08. could check
ShockSoc	0:375ecd0ed73d	107	if (LPC_I2C1->I2STAT != 0x08) {
ShockSoc	0:375ecd0ed73d	108	printf("RSTART %x\r\n",LPC_I2C1->I2STAT);
ShockSoc	0:375ecd0ed73d	109	//stop if failed
ShockSoc	0:375ecd0ed73d	110	LPC_I2C1->I2CONSET = 0x10;
ShockSoc	0:375ecd0ed73d	111	return -1;
ShockSoc	0:375ecd0ed73d	112	}
ShockSoc	0:375ecd0ed73d	113
ShockSoc	0:375ecd0ed73d	114	//clear start condition
ShockSoc	0:375ecd0ed73d	115	LPC_I2C1->I2CONCLR = 0x20;
ShockSoc	0:375ecd0ed73d	116
ShockSoc	0:375ecd0ed73d	117	//load i2dat with read bit set
ShockSoc	0:375ecd0ed73d	118	LPC_I2C1->I2DAT = address \| 0x1;
ShockSoc	0:375ecd0ed73d	119
ShockSoc	0:375ecd0ed73d	120	//reset si
ShockSoc	0:375ecd0ed73d	121	LPC_I2C1->I2CONCLR = 0x08;
ShockSoc	0:375ecd0ed73d	122
ShockSoc	0:375ecd0ed73d	123	//block until interrupt
ShockSoc	0:375ecd0ed73d	124	while ((LPC_I2C1->I2CONSET & 0x8) != 0x8) {}
ShockSoc	0:375ecd0ed73d	125
ShockSoc	0:375ecd0ed73d	126	//i2stat should be 0x40 - ack received
ShockSoc	0:375ecd0ed73d	127	if (LPC_I2C1->I2STAT != 0x40) {
ShockSoc	0:375ecd0ed73d	128	printf("RADD %x\r\n",LPC_I2C1->I2STAT);
ShockSoc	0:375ecd0ed73d	129	//stop
ShockSoc	0:375ecd0ed73d	130	LPC_I2C1->I2CONSET = 0x10;
ShockSoc	0:375ecd0ed73d	131	return -1;
ShockSoc	0:375ecd0ed73d	132	}
ShockSoc	0:375ecd0ed73d	133
ShockSoc	0:375ecd0ed73d	134	for (int i=0; i<length-1; i++) {
ShockSoc	0:375ecd0ed73d	135
ShockSoc	0:375ecd0ed73d	136	//ack next byte
ShockSoc	0:375ecd0ed73d	137	LPC_I2C1->I2CONSET = 0x4;
ShockSoc	0:375ecd0ed73d	138
ShockSoc	0:375ecd0ed73d	139	//reset si
ShockSoc	0:375ecd0ed73d	140	LPC_I2C1->I2CONCLR = 0x08;
ShockSoc	0:375ecd0ed73d	141
ShockSoc	0:375ecd0ed73d	142	//block until interrupt
ShockSoc	0:375ecd0ed73d	143	while ((LPC_I2C1->I2CONSET & 0x8) != 0x8) {}
ShockSoc	0:375ecd0ed73d	144
ShockSoc	0:375ecd0ed73d	145	//i2stat should be 0x50, byte received, ack sent
ShockSoc	0:375ecd0ed73d	146	if (LPC_I2C1->I2STAT != 0x50) {
ShockSoc	0:375ecd0ed73d	147	printf("rDATA%d %x\r\n",i,LPC_I2C1->I2STAT);
ShockSoc	0:375ecd0ed73d	148	//stop
ShockSoc	0:375ecd0ed73d	149	LPC_I2C1->I2CONSET = 0x10;
ShockSoc	0:375ecd0ed73d	150	return -1;
ShockSoc	0:375ecd0ed73d	151	}
ShockSoc	0:375ecd0ed73d	152
ShockSoc	0:375ecd0ed73d	153	data[i] = LPC_I2C1->I2DAT;
ShockSoc	0:375ecd0ed73d	154	}
ShockSoc	0:375ecd0ed73d	155
ShockSoc	0:375ecd0ed73d	156	//last byte
ShockSoc	0:375ecd0ed73d	157	//nack next byte
ShockSoc	0:375ecd0ed73d	158	LPC_I2C1->I2CONCLR = 0x4;
ShockSoc	0:375ecd0ed73d	159
ShockSoc	0:375ecd0ed73d	160	//reset si
ShockSoc	0:375ecd0ed73d	161	LPC_I2C1->I2CONCLR = 0x08;
ShockSoc	0:375ecd0ed73d	162
ShockSoc	0:375ecd0ed73d	163	//block until interrupt
ShockSoc	0:375ecd0ed73d	164	while ((LPC_I2C1->I2CONSET & 0x8) != 0x8) {}
ShockSoc	0:375ecd0ed73d	165
ShockSoc	0:375ecd0ed73d	166	//i2stat should be 0x58, byte received, nack sent
ShockSoc	0:375ecd0ed73d	167	if (LPC_I2C1->I2STAT != 0x58) {
ShockSoc	0:375ecd0ed73d	168	printf("lastd %x\r\n",LPC_I2C1->I2STAT);
ShockSoc	0:375ecd0ed73d	169	//stop
ShockSoc	0:375ecd0ed73d	170	LPC_I2C1->I2CONSET = 0x10;
ShockSoc	0:375ecd0ed73d	171	return -1;
ShockSoc	0:375ecd0ed73d	172	}
ShockSoc	0:375ecd0ed73d	173
ShockSoc	0:375ecd0ed73d	174	data[length-1] = LPC_I2C1->I2DAT;
ShockSoc	0:375ecd0ed73d	175
ShockSoc	0:375ecd0ed73d	176	//stop
ShockSoc	0:375ecd0ed73d	177	LPC_I2C1->I2CONSET = 0x10;
ShockSoc	0:375ecd0ed73d	178
ShockSoc	0:375ecd0ed73d	179	//reset si
ShockSoc	0:375ecd0ed73d	180	LPC_I2C1->I2CONCLR = 0x08;
ShockSoc	0:375ecd0ed73d	181
ShockSoc	0:375ecd0ed73d	182	return 0;
ShockSoc	0:375ecd0ed73d	183
ShockSoc	0:375ecd0ed73d	184	}

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Type:	Library
Created:	12 May 2011
Imports:	90
Forks:	0
Commits:	1
Dependents:	1
Dependencies:	0
Followers:	8

I2CR.cpp@0:375ecd0ed73d, 2011-05-12 (annotated)

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