audio_FFT - Read an audio signal from the ADC, write it out t…

Users » jcobb » Code » audio_FFT

James Cobb / Mbed 2 deprecated audio_FFT

Read an audio signal from the ADC, write it out to a file on the filestytem and perform a 1024 point FFT, writing frequency data to a csv file

Dependencies: mbed

ADC_full/adc.cpp@0:5b7b619f59cd, 2010-03-21 (annotated)

Committer:: jcobb
Date:: Sun Mar 21 18:06:46 2010 +0000
Revision:: 0:5b7b619f59cd

Who changed what in which revision?

User	Revision	Line number	New contents of line
jcobb	0:5b7b619f59cd	1	/* mbed Library - ADC
jcobb	0:5b7b619f59cd	2	* Copyright (c) 2010, sblandford
jcobb	0:5b7b619f59cd	3	* released under MIT license http://mbed.org/licence/mit
jcobb	0:5b7b619f59cd	4	*/
jcobb	0:5b7b619f59cd	5	#include "mbed.h"
jcobb	0:5b7b619f59cd	6	#include "adc.h"
jcobb	0:5b7b619f59cd	7
jcobb	0:5b7b619f59cd	8
jcobb	0:5b7b619f59cd	9	ADC *ADC::instance;
jcobb	0:5b7b619f59cd	10
jcobb	0:5b7b619f59cd	11	ADC::ADC(int sample_rate, int cclk_div)
jcobb	0:5b7b619f59cd	12	{
jcobb	0:5b7b619f59cd	13
jcobb	0:5b7b619f59cd	14	int i, adc_clk_freq, pclk, clock_div, max_div=1;
jcobb	0:5b7b619f59cd	15
jcobb	0:5b7b619f59cd	16	//Work out CCLK
jcobb	0:5b7b619f59cd	17	adc_clk_freq=CLKS_PER_SAMPLE*sample_rate;
jcobb	0:5b7b619f59cd	18	int m = (LPC_SC->PLL0CFG & 0xFFFF) + 1;
jcobb	0:5b7b619f59cd	19	int n = (LPC_SC->PLL0CFG >> 16) + 1;
jcobb	0:5b7b619f59cd	20	int cclkdiv = LPC_SC->CCLKCFG + 1;
jcobb	0:5b7b619f59cd	21	int Fcco = (2 * m * XTAL_FREQ) / n;
jcobb	0:5b7b619f59cd	22	int cclk = Fcco / cclkdiv;
jcobb	0:5b7b619f59cd	23
jcobb	0:5b7b619f59cd	24	//Power up the ADC
jcobb	0:5b7b619f59cd	25	LPC_SC->PCONP \|= (1 << 12);
jcobb	0:5b7b619f59cd	26	//Set clock at cclk / 1.
jcobb	0:5b7b619f59cd	27	LPC_SC->PCLKSEL0 &= ~(0x3 << 24);
jcobb	0:5b7b619f59cd	28	switch (cclk_div) {
jcobb	0:5b7b619f59cd	29	case 1:
jcobb	0:5b7b619f59cd	30	LPC_SC->PCLKSEL0 \|= 0x1 << 24;
jcobb	0:5b7b619f59cd	31	break;
jcobb	0:5b7b619f59cd	32	case 2:
jcobb	0:5b7b619f59cd	33	LPC_SC->PCLKSEL0 \|= 0x2 << 24;
jcobb	0:5b7b619f59cd	34	break;
jcobb	0:5b7b619f59cd	35	case 4:
jcobb	0:5b7b619f59cd	36	LPC_SC->PCLKSEL0 \|= 0x0 << 24;
jcobb	0:5b7b619f59cd	37	break;
jcobb	0:5b7b619f59cd	38	case 8:
jcobb	0:5b7b619f59cd	39	LPC_SC->PCLKSEL0 \|= 0x3 << 24;
jcobb	0:5b7b619f59cd	40	break;
jcobb	0:5b7b619f59cd	41	default:
jcobb	0:5b7b619f59cd	42	fprintf(stderr, "Warning: ADC CCLK clock divider must be 1, 2, 4 or 8. %u supplied.\n",
jcobb	0:5b7b619f59cd	43	cclk_div);
jcobb	0:5b7b619f59cd	44	fprintf(stderr, "Defaulting to 1.\n");
jcobb	0:5b7b619f59cd	45	LPC_SC->PCLKSEL0 \|= 0x1 << 24;
jcobb	0:5b7b619f59cd	46	break;
jcobb	0:5b7b619f59cd	47	}
jcobb	0:5b7b619f59cd	48	pclk = cclk / cclk_div;
jcobb	0:5b7b619f59cd	49	clock_div=pclk / adc_clk_freq;
jcobb	0:5b7b619f59cd	50
jcobb	0:5b7b619f59cd	51	if (clock_div > 0xFF) {
jcobb	0:5b7b619f59cd	52	fprintf(stderr, "Warning: Clock division is %u which is above 255 limit. Re-Setting at limit.\n",
jcobb	0:5b7b619f59cd	53	clock_div);
jcobb	0:5b7b619f59cd	54	clock_div=0xFF;
jcobb	0:5b7b619f59cd	55	}
jcobb	0:5b7b619f59cd	56	if (clock_div == 0) {
jcobb	0:5b7b619f59cd	57	fprintf(stderr, "Warning: Clock division is 0. Re-Setting to 1.\n");
jcobb	0:5b7b619f59cd	58	clock_div=1;
jcobb	0:5b7b619f59cd	59	}
jcobb	0:5b7b619f59cd	60
jcobb	0:5b7b619f59cd	61	_adc_clk_freq=pclk / clock_div;
jcobb	0:5b7b619f59cd	62	if (_adc_clk_freq > MAX_ADC_CLOCK) {
jcobb	0:5b7b619f59cd	63	fprintf(stderr, "Warning: Actual ADC sample rate of %u which is above %u limit\n",
jcobb	0:5b7b619f59cd	64	_adc_clk_freq / CLKS_PER_SAMPLE, MAX_ADC_CLOCK / CLKS_PER_SAMPLE);
jcobb	0:5b7b619f59cd	65	while ((pclk / max_div) > MAX_ADC_CLOCK) max_div++;
jcobb	0:5b7b619f59cd	66	fprintf(stderr, "Maximum recommended sample rate is %u\n", (pclk / max_div) / CLKS_PER_SAMPLE);
jcobb	0:5b7b619f59cd	67	}
jcobb	0:5b7b619f59cd	68
jcobb	0:5b7b619f59cd	69	LPC_ADC->ADCR =
jcobb	0:5b7b619f59cd	70	((clock_div - 1 ) << 8 ) \| //Clkdiv
jcobb	0:5b7b619f59cd	71	( 1 << 21 ); //A/D operational
jcobb	0:5b7b619f59cd	72
jcobb	0:5b7b619f59cd	73	//Default no channels enabled
jcobb	0:5b7b619f59cd	74	LPC_ADC->ADCR &= ~0xFF;
jcobb	0:5b7b619f59cd	75	//Default NULL global custom isr
jcobb	0:5b7b619f59cd	76	_adc_g_isr = NULL;
jcobb	0:5b7b619f59cd	77	//Initialize arrays
jcobb	0:5b7b619f59cd	78	for (i=7; i>=0; i--) {
jcobb	0:5b7b619f59cd	79	_adc_data[i] = 0;
jcobb	0:5b7b619f59cd	80	_adc_isr[i] = NULL;
jcobb	0:5b7b619f59cd	81	}
jcobb	0:5b7b619f59cd	82
jcobb	0:5b7b619f59cd	83
jcobb	0:5b7b619f59cd	84	//* Attach IRQ
jcobb	0:5b7b619f59cd	85	instance = this;
jcobb	0:5b7b619f59cd	86	NVIC_SetVector(ADC_IRQn, (uint32_t)&_adcisr);
jcobb	0:5b7b619f59cd	87
jcobb	0:5b7b619f59cd	88	//Disable global interrupt
jcobb	0:5b7b619f59cd	89	LPC_ADC->ADINTEN &= ~0x100;
jcobb	0:5b7b619f59cd	90
jcobb	0:5b7b619f59cd	91	};
jcobb	0:5b7b619f59cd	92
jcobb	0:5b7b619f59cd	93	void ADC::_adcisr(void)
jcobb	0:5b7b619f59cd	94	{
jcobb	0:5b7b619f59cd	95	instance->adcisr();
jcobb	0:5b7b619f59cd	96	}
jcobb	0:5b7b619f59cd	97
jcobb	0:5b7b619f59cd	98
jcobb	0:5b7b619f59cd	99	void ADC::adcisr(void)
jcobb	0:5b7b619f59cd	100	{
jcobb	0:5b7b619f59cd	101	uint32_t stat;
jcobb	0:5b7b619f59cd	102	int chan;
jcobb	0:5b7b619f59cd	103
jcobb	0:5b7b619f59cd	104	// Read status
jcobb	0:5b7b619f59cd	105	stat = LPC_ADC->ADSTAT;
jcobb	0:5b7b619f59cd	106	//Scan channels for over-run or done and update array
jcobb	0:5b7b619f59cd	107	if (stat & 0x0101) _adc_data[0] = LPC_ADC->ADDR0;
jcobb	0:5b7b619f59cd	108	if (stat & 0x0202) _adc_data[1] = LPC_ADC->ADDR1;
jcobb	0:5b7b619f59cd	109	if (stat & 0x0404) _adc_data[2] = LPC_ADC->ADDR2;
jcobb	0:5b7b619f59cd	110	if (stat & 0x0808) _adc_data[3] = LPC_ADC->ADDR3;
jcobb	0:5b7b619f59cd	111	if (stat & 0x1010) _adc_data[4] = LPC_ADC->ADDR4;
jcobb	0:5b7b619f59cd	112	if (stat & 0x2020) _adc_data[5] = LPC_ADC->ADDR5;
jcobb	0:5b7b619f59cd	113	if (stat & 0x4040) _adc_data[6] = LPC_ADC->ADDR6;
jcobb	0:5b7b619f59cd	114	if (stat & 0x8080) _adc_data[7] = LPC_ADC->ADDR7;
jcobb	0:5b7b619f59cd	115
jcobb	0:5b7b619f59cd	116	// Channel that triggered interrupt
jcobb	0:5b7b619f59cd	117	chan = (LPC_ADC->ADGDR >> 24) & 0x07;
jcobb	0:5b7b619f59cd	118	//User defined interrupt handlers
jcobb	0:5b7b619f59cd	119	if (_adc_isr[chan] != NULL)
jcobb	0:5b7b619f59cd	120	_adc_isr[chan](_adc_data[chan]);
jcobb	0:5b7b619f59cd	121	if (_adc_g_isr != NULL)
jcobb	0:5b7b619f59cd	122	_adc_g_isr(chan, _adc_data[chan]);
jcobb	0:5b7b619f59cd	123	return;
jcobb	0:5b7b619f59cd	124	}
jcobb	0:5b7b619f59cd	125
jcobb	0:5b7b619f59cd	126	int ADC::_pin_to_channel(PinName pin) {
jcobb	0:5b7b619f59cd	127	int chan;
jcobb	0:5b7b619f59cd	128	switch (pin) {
jcobb	0:5b7b619f59cd	129	case p15://=p0.23 of LPC1768
jcobb	0:5b7b619f59cd	130	default:
jcobb	0:5b7b619f59cd	131	chan=0;
jcobb	0:5b7b619f59cd	132	break;
jcobb	0:5b7b619f59cd	133	case p16://=p0.24 of LPC1768
jcobb	0:5b7b619f59cd	134	chan=1;
jcobb	0:5b7b619f59cd	135	break;
jcobb	0:5b7b619f59cd	136	case p17://=p0.25 of LPC1768
jcobb	0:5b7b619f59cd	137	chan=2;
jcobb	0:5b7b619f59cd	138	break;
jcobb	0:5b7b619f59cd	139	case p18://=p0.26 of LPC1768
jcobb	0:5b7b619f59cd	140	chan=3;
jcobb	0:5b7b619f59cd	141	break;
jcobb	0:5b7b619f59cd	142	case p19://=p1.30 of LPC1768
jcobb	0:5b7b619f59cd	143	chan=4;
jcobb	0:5b7b619f59cd	144	break;
jcobb	0:5b7b619f59cd	145	case p20://=p1.31 of LPC1768
jcobb	0:5b7b619f59cd	146	chan=5;
jcobb	0:5b7b619f59cd	147	break;
jcobb	0:5b7b619f59cd	148	}
jcobb	0:5b7b619f59cd	149	return(chan);
jcobb	0:5b7b619f59cd	150	}
jcobb	0:5b7b619f59cd	151
jcobb	0:5b7b619f59cd	152	PinName ADC::channel_to_pin(int chan) {
jcobb	0:5b7b619f59cd	153	const PinName pin[8]={p15, p16, p17, p18, p19, p20, p15, p15};
jcobb	0:5b7b619f59cd	154
jcobb	0:5b7b619f59cd	155	if ((chan < 0) \|\| (chan > 5))
jcobb	0:5b7b619f59cd	156	fprintf(stderr, "ADC channel %u is outside range available to MBED pins.\n", chan);
jcobb	0:5b7b619f59cd	157	return(pin[chan & 0x07]);
jcobb	0:5b7b619f59cd	158	}
jcobb	0:5b7b619f59cd	159
jcobb	0:5b7b619f59cd	160
jcobb	0:5b7b619f59cd	161	int ADC::channel_to_pin_number(int chan) {
jcobb	0:5b7b619f59cd	162	const int pin[8]={15, 16, 17, 18, 19, 20, 0, 0};
jcobb	0:5b7b619f59cd	163
jcobb	0:5b7b619f59cd	164	if ((chan < 0) \|\| (chan > 5))
jcobb	0:5b7b619f59cd	165	fprintf(stderr, "ADC channel %u is outside range available to MBED pins.\n", chan);
jcobb	0:5b7b619f59cd	166	return(pin[chan & 0x07]);
jcobb	0:5b7b619f59cd	167	}
jcobb	0:5b7b619f59cd	168
jcobb	0:5b7b619f59cd	169
jcobb	0:5b7b619f59cd	170	uint32_t ADC::_data_of_pin(PinName pin) {
jcobb	0:5b7b619f59cd	171	//If in burst mode and at least one interrupt enabled then
jcobb	0:5b7b619f59cd	172	//take all values from _adc_data
jcobb	0:5b7b619f59cd	173	if (burst() && (LPC_ADC->ADINTEN & 0x3F)) {
jcobb	0:5b7b619f59cd	174	return(_adc_data[_pin_to_channel(pin)]);
jcobb	0:5b7b619f59cd	175	} else {
jcobb	0:5b7b619f59cd	176	//Return current register value or last value from interrupt
jcobb	0:5b7b619f59cd	177	switch (pin) {
jcobb	0:5b7b619f59cd	178	case p15://=p0.23 of LPC1768
jcobb	0:5b7b619f59cd	179	default:
jcobb	0:5b7b619f59cd	180	return(LPC_ADC->ADINTEN & 0x01?_adc_data[0]:LPC_ADC->ADDR0);
jcobb	0:5b7b619f59cd	181	case p16://=p0.24 of LPC1768
jcobb	0:5b7b619f59cd	182	return(LPC_ADC->ADINTEN & 0x02?_adc_data[1]:LPC_ADC->ADDR1);
jcobb	0:5b7b619f59cd	183	case p17://=p0.25 of LPC1768
jcobb	0:5b7b619f59cd	184	return(LPC_ADC->ADINTEN & 0x04?_adc_data[2]:LPC_ADC->ADDR2);
jcobb	0:5b7b619f59cd	185	case p18://=p0.26 of LPC1768:
jcobb	0:5b7b619f59cd	186	return(LPC_ADC->ADINTEN & 0x08?_adc_data[3]:LPC_ADC->ADDR3);
jcobb	0:5b7b619f59cd	187	case p19://=p1.30 of LPC1768
jcobb	0:5b7b619f59cd	188	return(LPC_ADC->ADINTEN & 0x10?_adc_data[4]:LPC_ADC->ADDR4);
jcobb	0:5b7b619f59cd	189	case p20://=p1.31 of LPC1768
jcobb	0:5b7b619f59cd	190	return(LPC_ADC->ADINTEN & 0x20?_adc_data[5]:LPC_ADC->ADDR5);
jcobb	0:5b7b619f59cd	191	}
jcobb	0:5b7b619f59cd	192	}
jcobb	0:5b7b619f59cd	193	}
jcobb	0:5b7b619f59cd	194
jcobb	0:5b7b619f59cd	195	//Enable or disable an ADC pin
jcobb	0:5b7b619f59cd	196	void ADC::setup(PinName pin, int state) {
jcobb	0:5b7b619f59cd	197	int chan;
jcobb	0:5b7b619f59cd	198	chan=_pin_to_channel(pin);
jcobb	0:5b7b619f59cd	199	if ((state & 1) == 1) {
jcobb	0:5b7b619f59cd	200	switch(pin) {
jcobb	0:5b7b619f59cd	201	case p15://=p0.23 of LPC1768
jcobb	0:5b7b619f59cd	202	default:
jcobb	0:5b7b619f59cd	203	LPC_PINCON->PINSEL1 &= ~((unsigned int)0x3 << 14);
jcobb	0:5b7b619f59cd	204	LPC_PINCON->PINSEL1 \|= (unsigned int)0x1 << 14;
jcobb	0:5b7b619f59cd	205	LPC_PINCON->PINMODE1 &= ~((unsigned int)0x3 << 14);
jcobb	0:5b7b619f59cd	206	LPC_PINCON->PINMODE1 \|= (unsigned int)0x2 << 14;
jcobb	0:5b7b619f59cd	207	break;
jcobb	0:5b7b619f59cd	208	case p16://=p0.24 of LPC1768
jcobb	0:5b7b619f59cd	209	LPC_PINCON->PINSEL1 &= ~((unsigned int)0x3 << 16);
jcobb	0:5b7b619f59cd	210	LPC_PINCON->PINSEL1 \|= (unsigned int)0x1 << 16;
jcobb	0:5b7b619f59cd	211	LPC_PINCON->PINMODE1 &= ~((unsigned int)0x3 << 16);
jcobb	0:5b7b619f59cd	212	LPC_PINCON->PINMODE1 \|= (unsigned int)0x2 << 16;
jcobb	0:5b7b619f59cd	213	break;
jcobb	0:5b7b619f59cd	214	case p17://=p0.25 of LPC1768
jcobb	0:5b7b619f59cd	215	LPC_PINCON->PINSEL1 &= ~((unsigned int)0x3 << 18);
jcobb	0:5b7b619f59cd	216	LPC_PINCON->PINSEL1 \|= (unsigned int)0x1 << 18;
jcobb	0:5b7b619f59cd	217	LPC_PINCON->PINMODE1 &= ~((unsigned int)0x3 << 18);
jcobb	0:5b7b619f59cd	218	LPC_PINCON->PINMODE1 \|= (unsigned int)0x2 << 18;
jcobb	0:5b7b619f59cd	219	break;
jcobb	0:5b7b619f59cd	220	case p18://=p0.26 of LPC1768:
jcobb	0:5b7b619f59cd	221	LPC_PINCON->PINSEL1 &= ~((unsigned int)0x3 << 20);
jcobb	0:5b7b619f59cd	222	LPC_PINCON->PINSEL1 \|= (unsigned int)0x1 << 20;
jcobb	0:5b7b619f59cd	223	LPC_PINCON->PINMODE1 &= ~((unsigned int)0x3 << 20);
jcobb	0:5b7b619f59cd	224	LPC_PINCON->PINMODE1 \|= (unsigned int)0x2 << 20;
jcobb	0:5b7b619f59cd	225	break;
jcobb	0:5b7b619f59cd	226	case p19://=p1.30 of LPC1768
jcobb	0:5b7b619f59cd	227	LPC_PINCON->PINSEL3 &= ~((unsigned int)0x3 << 28);
jcobb	0:5b7b619f59cd	228	LPC_PINCON->PINSEL3 \|= (unsigned int)0x3 << 28;
jcobb	0:5b7b619f59cd	229	LPC_PINCON->PINMODE3 &= ~((unsigned int)0x3 << 28);
jcobb	0:5b7b619f59cd	230	LPC_PINCON->PINMODE3 \|= (unsigned int)0x2 << 28;
jcobb	0:5b7b619f59cd	231	break;
jcobb	0:5b7b619f59cd	232	case p20://=p1.31 of LPC1768
jcobb	0:5b7b619f59cd	233	LPC_PINCON->PINSEL3 &= ~((unsigned int)0x3 << 30);
jcobb	0:5b7b619f59cd	234	LPC_PINCON->PINSEL3 \|= (unsigned int)0x3 << 30;
jcobb	0:5b7b619f59cd	235	LPC_PINCON->PINMODE3 &= ~((unsigned int)0x3 << 30);
jcobb	0:5b7b619f59cd	236	LPC_PINCON->PINMODE3 \|= (unsigned int)0x2 << 30;
jcobb	0:5b7b619f59cd	237	break;
jcobb	0:5b7b619f59cd	238	}
jcobb	0:5b7b619f59cd	239	//Only one channel can be selected at a time if not in burst mode
jcobb	0:5b7b619f59cd	240	if (!burst()) LPC_ADC->ADCR &= ~0xFF;
jcobb	0:5b7b619f59cd	241	//Select channel
jcobb	0:5b7b619f59cd	242	LPC_ADC->ADCR \|= (1 << chan);
jcobb	0:5b7b619f59cd	243	}
jcobb	0:5b7b619f59cd	244	else {
jcobb	0:5b7b619f59cd	245	switch(pin) {
jcobb	0:5b7b619f59cd	246	case p15://=p0.23 of LPC1768
jcobb	0:5b7b619f59cd	247	default:
jcobb	0:5b7b619f59cd	248	LPC_PINCON->PINSEL1 &= ~((unsigned int)0x3 << 14);
jcobb	0:5b7b619f59cd	249	LPC_PINCON->PINMODE1 &= ~((unsigned int)0x3 << 14);
jcobb	0:5b7b619f59cd	250	break;
jcobb	0:5b7b619f59cd	251	case p16://=p0.24 of LPC1768
jcobb	0:5b7b619f59cd	252	LPC_PINCON->PINSEL1 &= ~((unsigned int)0x3 << 16);
jcobb	0:5b7b619f59cd	253	LPC_PINCON->PINMODE1 &= ~((unsigned int)0x3 << 16);
jcobb	0:5b7b619f59cd	254	break;
jcobb	0:5b7b619f59cd	255	case p17://=p0.25 of LPC1768
jcobb	0:5b7b619f59cd	256	LPC_PINCON->PINSEL1 &= ~((unsigned int)0x3 << 18);
jcobb	0:5b7b619f59cd	257	LPC_PINCON->PINMODE1 &= ~((unsigned int)0x3 << 18);
jcobb	0:5b7b619f59cd	258	break;
jcobb	0:5b7b619f59cd	259	case p18://=p0.26 of LPC1768:
jcobb	0:5b7b619f59cd	260	LPC_PINCON->PINSEL1 &= ~((unsigned int)0x3 << 20);
jcobb	0:5b7b619f59cd	261	LPC_PINCON->PINMODE1 &= ~((unsigned int)0x3 << 20);
jcobb	0:5b7b619f59cd	262	break;
jcobb	0:5b7b619f59cd	263	case p19://=p1.30 of LPC1768
jcobb	0:5b7b619f59cd	264	LPC_PINCON->PINSEL3 &= ~((unsigned int)0x3 << 28);
jcobb	0:5b7b619f59cd	265	LPC_PINCON->PINMODE3 &= ~((unsigned int)0x3 << 28);
jcobb	0:5b7b619f59cd	266	break;
jcobb	0:5b7b619f59cd	267	case p20://=p1.31 of LPC1768
jcobb	0:5b7b619f59cd	268	LPC_PINCON->PINSEL3 &= ~((unsigned int)0x3 << 30);
jcobb	0:5b7b619f59cd	269	LPC_PINCON->PINMODE3 &= ~((unsigned int)0x3 << 30);
jcobb	0:5b7b619f59cd	270	break;
jcobb	0:5b7b619f59cd	271	}
jcobb	0:5b7b619f59cd	272	LPC_ADC->ADCR &= ~(1 << chan);
jcobb	0:5b7b619f59cd	273	}
jcobb	0:5b7b619f59cd	274	}
jcobb	0:5b7b619f59cd	275	//Return channel enabled/disabled state
jcobb	0:5b7b619f59cd	276	int ADC::setup(PinName pin) {
jcobb	0:5b7b619f59cd	277	int chan;
jcobb	0:5b7b619f59cd	278
jcobb	0:5b7b619f59cd	279	chan = _pin_to_channel(pin);
jcobb	0:5b7b619f59cd	280	return((LPC_ADC->ADCR & (1 << chan)) >> chan);
jcobb	0:5b7b619f59cd	281	}
jcobb	0:5b7b619f59cd	282
jcobb	0:5b7b619f59cd	283	//Select channel already setup
jcobb	0:5b7b619f59cd	284	void ADC::select(PinName pin) {
jcobb	0:5b7b619f59cd	285	int chan;
jcobb	0:5b7b619f59cd	286
jcobb	0:5b7b619f59cd	287	//Only one channel can be selected at a time if not in burst mode
jcobb	0:5b7b619f59cd	288	if (!burst()) LPC_ADC->ADCR &= ~0xFF;
jcobb	0:5b7b619f59cd	289	//Select channel
jcobb	0:5b7b619f59cd	290	chan = _pin_to_channel(pin);
jcobb	0:5b7b619f59cd	291	LPC_ADC->ADCR \|= (1 << chan);
jcobb	0:5b7b619f59cd	292	}
jcobb	0:5b7b619f59cd	293
jcobb	0:5b7b619f59cd	294	//Enable or disable burst mode
jcobb	0:5b7b619f59cd	295	void ADC::burst(int state) {
jcobb	0:5b7b619f59cd	296	if ((state & 1) == 1) {
jcobb	0:5b7b619f59cd	297	if (startmode(0) != 0)
jcobb	0:5b7b619f59cd	298	fprintf(stderr, "Warning. startmode is %u. Must be 0 for burst mode.\n", startmode(0));
jcobb	0:5b7b619f59cd	299	LPC_ADC->ADCR \|= (1 << 16);
jcobb	0:5b7b619f59cd	300	}
jcobb	0:5b7b619f59cd	301	else
jcobb	0:5b7b619f59cd	302	LPC_ADC->ADCR &= ~(1 << 16);
jcobb	0:5b7b619f59cd	303	}
jcobb	0:5b7b619f59cd	304	//Return burst mode state
jcobb	0:5b7b619f59cd	305	int ADC::burst(void) {
jcobb	0:5b7b619f59cd	306	return((LPC_ADC->ADCR & (1 << 16)) >> 16);
jcobb	0:5b7b619f59cd	307	}
jcobb	0:5b7b619f59cd	308
jcobb	0:5b7b619f59cd	309	//Set startmode and edge
jcobb	0:5b7b619f59cd	310	void ADC::startmode(int mode, int edge) {
jcobb	0:5b7b619f59cd	311	int lpc_adc_temp;
jcobb	0:5b7b619f59cd	312
jcobb	0:5b7b619f59cd	313	//Reset start mode and edge bit,
jcobb	0:5b7b619f59cd	314	lpc_adc_temp = LPC_ADC->ADCR & ~(0x0F << 24);
jcobb	0:5b7b619f59cd	315	//Write with new values
jcobb	0:5b7b619f59cd	316	lpc_adc_temp \|= ((mode & 7) << 24) \| ((edge & 1) << 27);
jcobb	0:5b7b619f59cd	317	LPC_ADC->ADCR = lpc_adc_temp;
jcobb	0:5b7b619f59cd	318	}
jcobb	0:5b7b619f59cd	319
jcobb	0:5b7b619f59cd	320	//Return startmode state according to mode_edge=0: mode and mode_edge=1: edge
jcobb	0:5b7b619f59cd	321	int ADC::startmode(int mode_edge){
jcobb	0:5b7b619f59cd	322	switch (mode_edge) {
jcobb	0:5b7b619f59cd	323	case 0:
jcobb	0:5b7b619f59cd	324	default:
jcobb	0:5b7b619f59cd	325	return((LPC_ADC->ADCR >> 24) & 0x07);
jcobb	0:5b7b619f59cd	326	case 1:
jcobb	0:5b7b619f59cd	327	return((LPC_ADC->ADCR >> 27) & 0x01);
jcobb	0:5b7b619f59cd	328	}
jcobb	0:5b7b619f59cd	329	}
jcobb	0:5b7b619f59cd	330
jcobb	0:5b7b619f59cd	331	//Start ADC conversion
jcobb	0:5b7b619f59cd	332	void ADC::start(void) {
jcobb	0:5b7b619f59cd	333	startmode(1,0);
jcobb	0:5b7b619f59cd	334	}
jcobb	0:5b7b619f59cd	335
jcobb	0:5b7b619f59cd	336
jcobb	0:5b7b619f59cd	337	//Set interrupt enable/disable for pin to state
jcobb	0:5b7b619f59cd	338	void ADC::interrupt_state(PinName pin, int state) {
jcobb	0:5b7b619f59cd	339	int chan;
jcobb	0:5b7b619f59cd	340
jcobb	0:5b7b619f59cd	341	chan = _pin_to_channel(pin);
jcobb	0:5b7b619f59cd	342	if (state == 1) {
jcobb	0:5b7b619f59cd	343	LPC_ADC->ADINTEN &= ~0x100;
jcobb	0:5b7b619f59cd	344	LPC_ADC->ADINTEN \|= 1 << chan;
jcobb	0:5b7b619f59cd	345	/* Enable the ADC Interrupt */
jcobb	0:5b7b619f59cd	346	NVIC_EnableIRQ(ADC_IRQn);
jcobb	0:5b7b619f59cd	347	} else {
jcobb	0:5b7b619f59cd	348	LPC_ADC->ADINTEN &= ~( 1 << chan );
jcobb	0:5b7b619f59cd	349	//Disable interrrupt if no active pins left
jcobb	0:5b7b619f59cd	350	if ((LPC_ADC->ADINTEN & 0xFF) == 0)
jcobb	0:5b7b619f59cd	351	NVIC_DisableIRQ(ADC_IRQn);
jcobb	0:5b7b619f59cd	352	}
jcobb	0:5b7b619f59cd	353	}
jcobb	0:5b7b619f59cd	354
jcobb	0:5b7b619f59cd	355	//Return enable/disable state of interrupt for pin
jcobb	0:5b7b619f59cd	356	int ADC::interrupt_state(PinName pin) {
jcobb	0:5b7b619f59cd	357	int chan;
jcobb	0:5b7b619f59cd	358
jcobb	0:5b7b619f59cd	359	chan = _pin_to_channel(pin);
jcobb	0:5b7b619f59cd	360	return((LPC_ADC->ADINTEN >> chan) & 0x01);
jcobb	0:5b7b619f59cd	361	}
jcobb	0:5b7b619f59cd	362
jcobb	0:5b7b619f59cd	363
jcobb	0:5b7b619f59cd	364	//Attach custom interrupt handler replacing default
jcobb	0:5b7b619f59cd	365	void ADC::attach(void(*fptr)(void)) {
jcobb	0:5b7b619f59cd	366	//* Attach IRQ
jcobb	0:5b7b619f59cd	367	NVIC_SetVector(ADC_IRQn, (uint32_t)fptr);
jcobb	0:5b7b619f59cd	368	}
jcobb	0:5b7b619f59cd	369
jcobb	0:5b7b619f59cd	370	//Restore default interrupt handler
jcobb	0:5b7b619f59cd	371	void ADC::detach(void) {
jcobb	0:5b7b619f59cd	372	//* Attach IRQ
jcobb	0:5b7b619f59cd	373	instance = this;
jcobb	0:5b7b619f59cd	374	NVIC_SetVector(ADC_IRQn, (uint32_t)&_adcisr);
jcobb	0:5b7b619f59cd	375	}
jcobb	0:5b7b619f59cd	376
jcobb	0:5b7b619f59cd	377
jcobb	0:5b7b619f59cd	378	//Append interrupt handler for pin to function isr
jcobb	0:5b7b619f59cd	379	void ADC::append(PinName pin, void(*fptr)(uint32_t value)) {
jcobb	0:5b7b619f59cd	380	int chan;
jcobb	0:5b7b619f59cd	381
jcobb	0:5b7b619f59cd	382	chan = _pin_to_channel(pin);
jcobb	0:5b7b619f59cd	383	_adc_isr[chan] = fptr;
jcobb	0:5b7b619f59cd	384	}
jcobb	0:5b7b619f59cd	385
jcobb	0:5b7b619f59cd	386	//Append interrupt handler for pin to function isr
jcobb	0:5b7b619f59cd	387	void ADC::unappend(PinName pin) {
jcobb	0:5b7b619f59cd	388	int chan;
jcobb	0:5b7b619f59cd	389
jcobb	0:5b7b619f59cd	390	chan = _pin_to_channel(pin);
jcobb	0:5b7b619f59cd	391	_adc_isr[chan] = NULL;
jcobb	0:5b7b619f59cd	392	}
jcobb	0:5b7b619f59cd	393
jcobb	0:5b7b619f59cd	394	//Unappend global interrupt handler to function isr
jcobb	0:5b7b619f59cd	395	void ADC::append(void(*fptr)(int chan, uint32_t value)) {
jcobb	0:5b7b619f59cd	396	_adc_g_isr = fptr;
jcobb	0:5b7b619f59cd	397	}
jcobb	0:5b7b619f59cd	398
jcobb	0:5b7b619f59cd	399	//Detach global interrupt handler to function isr
jcobb	0:5b7b619f59cd	400	void ADC::unappend() {
jcobb	0:5b7b619f59cd	401	_adc_g_isr = NULL;
jcobb	0:5b7b619f59cd	402	}
jcobb	0:5b7b619f59cd	403
jcobb	0:5b7b619f59cd	404	//Set ADC offset
jcobb	0:5b7b619f59cd	405	void offset(int offset) {
jcobb	0:5b7b619f59cd	406	LPC_ADC->ADTRM &= ~(0x07 << 4);
jcobb	0:5b7b619f59cd	407	LPC_ADC->ADTRM \|= (offset & 0x07) << 4;
jcobb	0:5b7b619f59cd	408	}
jcobb	0:5b7b619f59cd	409
jcobb	0:5b7b619f59cd	410	//Return current ADC offset
jcobb	0:5b7b619f59cd	411	int offset(void) {
jcobb	0:5b7b619f59cd	412	return((LPC_ADC->ADTRM >> 4) & 0x07);
jcobb	0:5b7b619f59cd	413	}
jcobb	0:5b7b619f59cd	414
jcobb	0:5b7b619f59cd	415	//Return value of ADC on pin
jcobb	0:5b7b619f59cd	416	int ADC::read(PinName pin) {
jcobb	0:5b7b619f59cd	417	//Reset DONE and OVERRUN flags of interrupt handled ADC data
jcobb	0:5b7b619f59cd	418	_adc_data[_pin_to_channel(pin)] &= ~(((uint32_t)0x01 << 31) \| ((uint32_t)0x01 << 30));
jcobb	0:5b7b619f59cd	419	//Return value
jcobb	0:5b7b619f59cd	420	return((_data_of_pin(pin) >> 4) & 0xFFF);
jcobb	0:5b7b619f59cd	421	}
jcobb	0:5b7b619f59cd	422
jcobb	0:5b7b619f59cd	423	//Return DONE flag of ADC on pin
jcobb	0:5b7b619f59cd	424	int ADC::done(PinName pin) {
jcobb	0:5b7b619f59cd	425	return((_data_of_pin(pin) >> 31) & 0x01);
jcobb	0:5b7b619f59cd	426	}
jcobb	0:5b7b619f59cd	427
jcobb	0:5b7b619f59cd	428	//Return OVERRUN flag of ADC on pin
jcobb	0:5b7b619f59cd	429	int ADC::overrun(PinName pin) {
jcobb	0:5b7b619f59cd	430	return((_data_of_pin(pin) >> 30) & 0x01);
jcobb	0:5b7b619f59cd	431	}
jcobb	0:5b7b619f59cd	432
jcobb	0:5b7b619f59cd	433	int ADC::actual_adc_clock(void) {
jcobb	0:5b7b619f59cd	434	return(_adc_clk_freq);
jcobb	0:5b7b619f59cd	435	}
jcobb	0:5b7b619f59cd	436
jcobb	0:5b7b619f59cd	437	int ADC::actual_sample_rate(void) {
jcobb	0:5b7b619f59cd	438	return(_adc_clk_freq / CLKS_PER_SAMPLE);
jcobb	0:5b7b619f59cd	439	}

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Type:	Program
Mbed OS support:	Mbed 2 deprecated
Created:	21 Mar 2010
Imports:	810
Forks:	1
Commits:	1
Dependents:	0
Dependencies:	1
Followers:	23

ADC_full/adc.cpp@0:5b7b619f59cd, 2010-03-21 (annotated)

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